The history of our families is an allure that is becoming increasingly accessible as mountains of historical documents are digitised and made public.

But while uncovering the secrets of your family heritage may surprise and even impress, there are some dark corners our great-grandparents may have preferred to have kept hidden.

In a time before brain scans and cognitive therapy, the mentally ill were often labelled as lunatics and consigned to the concrete floors of 19th century asylums.

A century later and almost 150,000 historical records including patient registers, newspaper clippings, photos and even suicide notes, have been collected and digitised by the genealogy website Ancestry.

An insight into forgotten family histories

Built in the early 1860s, the sprawling Aradale Lunatic Asylum in Ararat housed Victoria's mentally ill for 126 years. ( Supplied: Ancestry )

Content Acquisition Manager for Ancestry Jason Reeve said his team worked with the Public Records Office of Victoria to access and digitise almost 50,000 records and 97,000 images from 15 institutions.

"This means 50,000 individuals," Mr Reeve said.

"The record sets that do come to light and what you find in them that you're not expecting to find, makes every bit of information so precious."

Mr Reeve said while the records taken from 1853 to 1940 were generally "not cheerful", they offered critical information that would be otherwise left unnoticed.

"When you're looking at family history, it's not just about the good things, the good stories, the fun stories, there's also the challenges that families had," he said.

"When you look back a couple of generations you start to find that people didn't talk about family history generally, let alone challenges in their family history.

Mont Park Hospital for the Insane opened in 1912 and was considered a leader in the treatment of mental illness during the 1930s and 40s. ( Supplied: Ancestry )

"So something like asylum records can bring to light challenges families had or where relatives were at a particular time that might not have been discussed."

Mr Reeve said the records shed light on how far common understandings of mental health have progressed.

"There are some records that pertain to people being in those institutions which in the modern world, they wouldn't be there.

"It also helps us appreciate where we are today."

Records were collected from Victoria's institutions in Ararat, Ballarat, Belmont, Cloverdale, Kew, Lara, Merton, Mont Park, Mt Ida, Northcote, St Helens, Yarra Bend and 'the Tofts' in Frankston.

Mental turmoil in a time before modern treatments

One of the almost 50,000 cases catalogued involves Alfred John Williams, who was institutionalised at the Yarra Bend Asylum after being found in a state of apparent amnesia near Werribee in 1896.

Newspaper reports described Mr Williams as being in a "strange and frightened manner", unable to recognise his uncle and brother-in-law or recall his name or where he came from.

The records of Alfred John Williams include his patient register and a suicide note. ( Supplied: Ancestry )

A scrambled suicide note to his wife is included with Mr Williams patient records, in which he writes: "I am tired of my life. You do not know what my feelings are or you would pity me when I hear Mother speak of her troubles.

"I am a burden on everyone In [sic] think it is best if I were gone I have kissed the children. You must kiss poor Herbert for me. Ask them to forgive me."

The "form of insanity" listed on Mr Williams patient record is that of 'Melancholia' — a condition no longer recognised as a separate mental illness by most psychiatric associations.

It's not clear whether Mr Williams wrote the suicide note before or after he was found with memory loss, but he was later discharged from Yarra Bend and returned to his family.

No need to feel ashamed

Neami National is a not-for-profit organisation that helps people with a mental illness reconnect with family, receive an education and community-based care.

Between 1982 and 1986, CEO Arthur Papakotsias trained and worked as a psychiatric nurse at the Larundel Mental Hospital, which was based on the same campus as the Mont Park Asylum and collectively housed up to 2,000 people.

"For a long time those institutions represented a view of 'out of sight, out of mind'," Mr Papakotsias said.

"I met people who had spent the better part of their adult life there and were in their 50s and 60s."

Mr Papakotsias said he used to affectionately refer to Melbourne's Larundel as the 'psychopolis' — as a community within a community that had its own standards and rules.

"What I saw was a mixture of really excellent practice by a lot of very young and highly motivated and aspirational staff, and I also saw some very bad practices from staff, and I'd have to say a number of them had been trained a number of decades ago," he said.

"In some cases there was a view of the 'us and them' and I think that's changed a lot in mental health."

Mr Papakotsias said the asylums and mental institutions of the 19th and 20th century represented society's intolerance but that relatives should not feel ashamed.

"For that person to not to feel ashamed that their relative was in there is an important stepping stone and I think that there was a lot of shame in mental illness in the past that's not as prevalent today," he said.

"The concept of being locked up in an institution as it was put many many years ago, was something that was seen as a personal weakness."

"We've still got a long way to go but I'd like to think people in society have moved on considerably from feeling like 'my grandfather or my uncle who was in an institution, I feel ashamed of them.'"

Ancestry plans to release the record set on Tuesday.