Ireland's biggest dog show will take place as usual this year on St Patrick's Day. For many decades any dog show could only be staged in Ireland under licence from the British Kennel Club. All that changed on October 16, 1920 when the Dublin Blue Terrier Club held a breed show in open defiance of the British regulation.

One of the club's members was a young man called Michael Collins. He may have been devoted to Kerry Blue Terriers, but Collins had a wide range of other interests.

In 1920, he was a member of Dail Eireann, as well as being the director of organisation and arms procurement for the Irish Republican Army. He was leading the IRA's military campaign against the British presence in Ireland, and Dublin Castle had offered a reward of £10,000 for any information leading to his capture or death.

The Kerry Blue dog had become a sort of "people's dog" for young nationalists like Collins. To begin with, the breed was not associated with the landed gentry - unlike Ireland's gun dogs and retrievers. It was considered "racy and of the soil", and conveyed a sense of sturdy independence. It also had the reputation of being a formidable fighting dog, and its combative and rebellious nature appealed to nationalists.

Membership of the Blue Terrier Club was not wholly confined to those who shared Collins's political views. In fact, a number of well-known Unionists and leading figures in the British administration in Ireland had also joined. One of these was the serving Under Secretary of State, Sir James McMahon. Another was Captain the Honourable Valentine Maurice Wyndham-Quin who was serving as a military attache in the Vice-Regal Lodge in Dublin's Phoenix Park.

It may seem strange that Collins would be a member of the same club as officials of the British Empire, and even stranger that he should have risked his life by attending an unlicensed dog show. However, Collins's attendance at the show is not so improbable as it may seem. When the British were searching for him all over Ireland, Collins adopted the bold strategy of "hiding in plain view". He believed - correctly - that the air of careless normality which he assumed was his best and most effective disguise. The Irish Kennel Club records that Michael Collins was the 18th person to register a dog with the Dublin Blue Terrier Club. He became a sort of ambassador for the breed, and was in the habit of giving presents of Kerry Blues to his friends - including some of those who would take the opposing side to him in Ireland's bitter Civil War. Collins later donated a trophy to the Terrier Club - the Micheal O Coileain Perpetual Cup - which is still competed for nowadays.

On St Patrick's Day in 1921, the Blue Terrier Club staged another breed show in Dublin. Once again, this was in open defiance of the British regulations. In fact, it was a double act of defiance since it took place on the same day that the British Kennel Club had organised its own dog show. By all accounts, the British event in Merrion Square was a damp squib compared to the Irish one.

Since then, there has only been one dog show in Ireland on Paddy's Day, and that one has been run by the Irish Kennel Club. Strangely, one thing that the British and Irish Kennel Club shows held in common was alcohol. At the start of the twentieth century, James O'Mara, an Irish Nationalist MP at Westminster, had grown alarmed by the amount of drink that was consumed in Ireland on our national saint's day - particularly, since this occurred during Lent. He introduced a Bill to the House of Commons that made it compulsory for all public houses in Ireland to close on March 17.

This legislation was not repealed until the early 1970s, and it meant that for most of the twentieth century it was illegal to buy alcohol in Ireland on Patrick's Day. However, certain exceptions were made, and alcoholic drink could still be served to bona fide members of the Kennel Club on the day of its annual show. Not surprisingly, the club could expect an influx of new members every March. Some of these had displayed little previous interest in dogs, but were known to be fond of drink. According to urban legend, Brendan Behan was in the habit of gathering up any stray mutt he could find and using it to blag his way into the members' lounge of the RDS. Patrick Kavanagh was also alleged to have paid a young woman for the "rent" of her dog on that one day every year.

When Michael Collins signed the Anglo-Irish Treaty the following year, he predicted that he was signing his own death warrant. In June of 1922, a civil war broke out in Ireland. Collins became commander-in-chief of Ireland's new National Army, and prosecuted the war with his customary zeal and vigour. But that did not mean he had forgotten the Kerry Blue Terrier. In fact, towards the end of 1922, he was drawing up plans for Dail Eireann to officially recognise the Kerry Blue as Ireland's National Dog. Sadly, before these plans could be realised, he was assassinated in the ambush at Beal na Blath.

Ireland now has one of the highest rates of dog ownership in Europe. Numerous breeds can be found on our small island, but only nine of them are native to this country.

There are four terriers: the Kerry Blue, the Glen of Imaal, the Irish Terrier and the Irish Soft-Coated Wheaten. There are three gun dogs: the Irish Red and White Setter, the Irish Red Setter and the Irish Water Spaniel. There are also two hounds: the Kerry Beagle and the Irish Wolfhound.

For me, the all-Red Setters are the catwalk models of their tribe: glamorous and effortlessly elegant, but with a touch of devilment, some might say madness, in their genetic mix. It is no surprise that owners of the reds have included Russian Tsars, US Presidents and Hollywood movie stars. It also seems appropriate that the dog favoured by Charles Stewart Parnell should be one of this breed. Indeed, Parnell insisted that his beloved setter stayed beside him while he lay on his death bed, forsaken by many of his erstwhile followers.

The red may be the most glamorous, but the most iconic of Irish dogs is undoubtedly the Wolfhound. This giant dog stalked through ancient Celtic mythology, and was renowned for its size, speed and strength. But, perhaps, this breed proved too effective for its own good, because by the end of the eighteenth century Irish wolves had been hunted to extinction. This had ominous implications for the Wolfhound. In fact, not long after wolves disappeared from Ireland, Wolfhounds are also believed to have become extinct. There were several attempts to resurrect the breed, and the most successful of these was made by a wealthy Englishman called George Graham. He had bought a large estate in rural Gloucestershire for the purpose of breeding Wolfhounds, and he pursued that goal with unwavering dedication for the next half-century. Since there were very few (if any) purebred specimens to be found in Ireland, Graham was compelled to use other breeds to create his ideal Wolfhound.

As a result, the dog we now regard as quintessentially Irish can count Russian, Scottish, Danish. English and even Tibetan dogs among its ancestors.

For some reason, the Wolfhound has proved of particular appeal to rock stars of a certain vintage. Owners of the breed have included Marc Bolan, the Bee Gees and Sting, while Van Morrison posed with two of them for the cover of his album Veedon Fleece.

There was a time when another Irish dog could be found in many of the royal palaces of Europe. The Habsburg emperors used the Irish Terrier as a hunting dog, and, when King Edward VII paid a state visit to Ireland in 1903, he brought his beloved Irish dog, Jack, with him. Unfortunately, Jack died within a few hours of setting his paws on Irish soil. Some interpreted this as a sign that his master was not welcome in Ireland, and as an omen for the future.

The Irish Terrier found a new role in World War I. When hostilities broke out in 1914, there was only one dog serving in the entire British Army. But, by the time the war ended, more than 20,000 dogs had been recruited by the Allied forces. Many of these were Irish Terriers. They were used to carry messages between frontline trenches, and also for scouting operations since they could use their acute sense of smell to detect enemy movements.

The Irish dogs were extremely popular with the Allied troops - who christened them the "Micks" - and helped to sustain morale in grim circumstances. They also killed many of the rats that infested the trenches and fed on the bodies in no-man's land. A large number of terriers never made it back to their homes in Ireland, and others suffered horrific injuries from bullets, bombs and mustard gas, with some even displaying the symptoms of what is now termed post-traumatic stress disorder.

Those that survived the carnage, and were able to return to Ireland came back to a changed political environment. In the aftermath of the Easter Rising, and the subsequent executions of its leaders, a wave of intense nationalist sentiment had swept over much of the island. The association of the Irish Terrier with the British Army had become a liability in many parts of Ireland. That may explain, in part, the dramatic decline in popularity of the breed.

Fads in dog ownership can change rapidly. One of the reasons that six of the nine native breeds of Ireland face possible extinction is because of the current fashion for so-called "teacups": miniature and toy breeds which are intended to be as small as possible (Paris Hilton is reported to have spent $20,000 on her latest tiny pooch). None of the Irish breeds could be described as a lapdog: even the Glen of Imaal Terrier, could not fit into anyone's handbag (unless they were a giant).

The only Irish dogs that are still connected to celebs are: Irish Wolfhounds, owned by Touched by an Angel star, Roma Downey; Wheaten Terriers, owned by singer-songwriter Josh Groban and Hollywood actress Amy Smart; and Irish Red Setters, owned by the comedian Alan Carr (who owns two) and by Gwyneth Paltrow (for which I am prepared to forgive a lot).

The Kerry Beagle was once the favourite hunting dog of the Irish landed gentry. However, during the Land War of the 1880s, there was an organised campaign to stop fox hunts crossing tenant farmers' land. Poisoned meat was laid along roads and fields for the Kerry Beagles to eat, and kennels were raided at night and the unfortunate hounds had their throats cut. Today, there is only one unified pack of these lovely dogs in the whole of Ireland.

The popularity of some Irish dogs has also been affected by the emergence of newer breeds. The Irish Water Spaniel, for example, may well be our oldest native dog. Its topknot of loose curls, often falling over its eyes, can make the dog look like a member of some strange Rastafarian cult. However, appearances can be misleading: in reality, the Water Spaniel is an exceptionally intelligent gun dog.

By the end of the nineteenth century, it had become one of the world's most popular hunting breeds. But, over a period of 50 years, a small group of British aristocrats had developed a rival breed. They intended that ownership of this dog would be confined to themselves and a select group of their friends. However, that restriction proved impossible to sustain, and the Labrador Retriever was eventually registered with the British Kennel Club in 1903.

Like the Irish spaniel, the Labrador is a gun dog. But, unlike the Irish breed, it has a short smooth coat that needs little maintenance. It also has a more placid temperament than the Irish dog, and may be better suited to being a family pet. Today, the Labrador is the world's most popular breed of dog, while the Irish Water Spaniel is rarely seen - even in its homeland. This raises an obvious question. If any, or all, of our native breeds of dog were to disappear, would it really matter?

It clearly wouldn't matter to any of the dogs. They are as indifferent to the fate of their breed as they are to their own appearance. However, I believe the loss of Ireland's native dogs should matter to the humans with whom they share this island. When any species of animal disappears, it is usually because it has been hunted to extinction, or because its natural habitats have disappeared. But we don't hunt domestic dogs, and their natural habitats are our homes.

We are fortunate in Ireland to have nine exceptional native breeds. Over the centuries, their stories have become inextricably linked to those of the human beings who also live in Ireland. These dogs form a integral part of our cultural heritage, bonding us with our past, and serving as living testaments to the social conditions and the human needs that bred them.

In that context, I think we should take whatever steps are necessary to ensure that each breed is preserved for future generations.

The Curious History of Irish Dogs, by David Blake Knox, is published by New Island, €20

Sunday Independent