The horrors of forcible feeding endured by imprisoned suffragettes on hunger strike are relatively well known; the image of rubber tubes being rammed down women's throats as they were held or tied down is a hard one to shake. Less widely documented have been the efforts made to protect the movement's leaders from arrest in the first place: of the 30-strong elite "bodyguard" trained to resist the police using the martial art jujutsu, and of the woman who taught them – Edith Garrud. But this Saturday, Islington council will unveil a People's Plaque, voted for by residents, at the house where this little-known suffragette lived in Thornhill Square, London.

One of the western world's first female martial arts instructors, Garrud, who died in 1971 aged 99, is thought to have learned jujutsu in the late 19th century. She began working with suffragettes between 1908 and 1911, eventually at her own women-only training hall, a room at the Palladium Academy dance school in Argyll Street.

When the government passed the notorious "Cat and Mouse Act" in 1913 – under which hunger strikers were released only to be rearrested when they had regained their strength – the Women's Social and Political Union responded by setting up a dedicated unit to protect Emmeline Pankhurst and other leaders from arrest.

Martial arts expert Tony Wolf, andauthor of a book about Edith Garrud aimed at teenage girls, says there was a "direct progression" from this job to that of official trainer of the bodyguard. "Members [of the bodyguard] had to be athletic and willing to face injury and arrest. She trained them in jujutsu at secret locations throughout London, and also taught them how to use wooden Indian clubs, which were concealed in their dresses and used as weapons against the truncheons of the police." Garrud, who was just 4ft 11in tall, seems to have embraced the spotlight, even before the bodyguard was formed. In 1910 she produced an illustrated article explaining how woman using the jujutsu methods had "brought great burly cowards nearly twice their size to their feet and made them howl for mercy."

"Woman is exposed to many perils nowadays, because so many who call themselves men are not worthy of that exalted title, and it is her duty to learn how to defend herself," she wrote, in the same year a Punch cartoon depicted policemen cowering before her.

But Tony Wolf cautions against romanticised images of suffragettes throwing officers around. "The bodyguard had some remarkable tactical victories using decoys and disguises," he says. "But the grim reality is that they were heavily outnumbered by the police and were often injured."