Fifty-one per cent of people questioned could not identify who Mary Queen of Scots was from her portrait, a survey commissioned by the University of Glasgow found.
Beyond her red hair, the survey found that Britons know very little about the Linlithgow Palace-born monarch and her history.
Mary Stewart became Queen of Scots on the death of her father James V in 1542, aged only six days old.
Raised in France from 1547, she returned to Scotland in 1561 following the death of her first husband, King Francis II.
Mary exercised direct personal control over Scotland for just six years from 1561 until 1567, when a coalition of nobility forced her to abdicate in favour of her infant son James.
Escaping to England in 1568, she spent the rest of her life in English captivity until her execution for treason against Elizabeth I in 1587 at the age of 44.
According to the survey, only 27% could correctly state how old she was when she was killed and just 18% knew she was just six days old when she became queen of Scotland.
A total of 62% were able to identify her famous red hair, and 63% of people who were asked knew she was accused of killing her second husband, Lord Darnley.
The University of Glasgow has now launched a new course, The Life and Afterlife of Mary Queen of Scots, which is free to access.
Dr Steven Reid, a senior lecturer in Scottish history at the university, and the course leader, said: “We’ve found over 2,000 different objects, ranging from art to personal relics, that tell us how Mary was remembered and how stories about her were told throughout centuries.
“These stories tell us as much about the cultural biases of the people who tell them – their views on gender, on religion, and on power, for example – as they do about how Mary has lived on in the popular imagination.”
The three-week course is available on the FutureLearn platform, and Astrid deRidder, the director of content at the company, said it “dives into the fascinating life and legacy of Mary Queen of Scots”.