Mary Beard, an only child, was born on 1 January 1955 in Much Wenlock, Shropshire. Her mother, Joyce Emily Beard, was a headmistress and an enthusiastic reader. Her father, Roy Whitbread Beard, worked as an architect in Shrewsbury. She recalled him as “a raffish public-schoolboy type and a complete wastrel, but very engaging”.

Between 1979 and 1983, Beard lectured in Classics at King’s College, London; she returned to Cambridge in 1984 as a Fellow of Newnham College and the only female lecturer in the Classics faculty. Rome in the Late Republic, which she co-wrote with Cambridge historian Michael Crawford, was published the following year.

Beard graduated from Cambridge with a Bachelor of Arts (BA) degree: as per tradition, her BA was later promoted to a Master of Arts (MA Cantab) degree. She remained at Cambridge for her Doctor of Philosophy (PhD) degree: she completed it in 1982 with a doctoral thesis titled The State Religion in the Late Roman Republic: A Study Based on the Works of Cicero.

Beard married Robin Cormack, a classicist and art historian, in 1985. Their daughter Zoe is an historian of South Sudan and their son Raphael is a scholar of Egyptian literature.

John Sturrock, Classics editor of The Times Literary Supplement, approached her for a review and brought her into literary journalism. Beard took over his role in 1992 at the request of Ferdinand Mount. In 1994 she made an early television appearance on an Open Media discussion for the BBC, Weird Thoughts, alongside Jenny Randles and James Randi among others.

In 2000, Beard revealed in an essay for the London Review of Books reviewing a book on rape that she too had been raped, in 1978.

In 2004, Beard became Professor of Classics at Cambridge. She was elected Visiting Sather Professor of Classical Literature for 2008–2009 at the University of California, Berkeley, where she delivered a series of lectures on “Roman Laughter”. In 2007–2008 Beard gave the Sigmund H. Danziger Jr. Memorial Lecture in the Humanities at the University of Chicago.

In December 2010, on BBC Two, Beard presented Pompeii: Life and Death in a Roman Town, submitting remains from the town to forensic tests, aiming to show a snapshot of the lives of the residents prior to the eruption of Mount Vesuvius in 79 CE. In 2011 she took part in a television series, Jamie’s Dream School on Channel 4, in which she taught classics to teenagers with no experience of academic success. Beard is a regular contributor to the BBC Radio 4 series, A Point of View, delivering essays on a broad range of topics including Miss World and the Oxbridge interview.

For BBC Two in 2012 she wrote and presented the three part television series, Meet the Romans with Mary Beard, which concerns how ordinary people lived in Rome, “the world’s first global metropolis”. The critic A. A. Gill reviewed the programme, writing mainly about her appearance (teeth, hair, and clothes), judging her “too ugly for television”. Beard admitted that his attack felt like a punch, but swiftly responded with a counter-attack on his intellectual abilities, accusing him of being part of “the blokeish culture that loves to decry clever women”. This exchange became the focus of a debate about older women on the public stage, with Beard saying she looked an ordinary woman of her age and “there are kids who turn on these programmes and see there’s another way of being a woman”, without Botox and hair dye. Charlotte Higgins assessed Beard as one of the rare academics who is both well respected by her peers and has a high profile in the media.

Beard is known for being active on Twitter, which she sees as part of her public role as an academic. Beard received considerable online abuse after she appeared on BBC’s Question Time from Lincolnshire in January 2013 and cast doubt on the negative rhetoric about immigrant workers living in the county. She asserted her right to express unpopular opinions and to present herself in public in a way she deemed authentic. On 4 August 2013, she received a bomb threat on Twitter, hours after the UK head of Twitter had apologised to women who had experienced abuse on the service. Beard said she did not think she was in physical danger, but considered it harassment and wanted to “make sure” that another case had been logged by the police. She has been praised for exposing “social media at its most revolting and misogynistic”.

In 2013 she presented Caligula with Mary Beard, describing the making of myths around leaders and dictators. Interviewers continued to ask about her self-presentation, and she reiterated that she had no intention of undergoing a make-over.

In April 2013 she was named as Royal Academy of Arts Professor of Ancient Literature. On 20 May 2019 Beard received an honorary degree from Yale University.

On 14 February 2014 Beard delivered a lecture on the public voice of women at the British Museum as part of the London Review of Books winter lecture series. “Oh Do Shut Up, Dear!”, shown on BBC Four a month later, started with the example of Telemachus, the son of Odysseus and Penelope, admonishing his mother to retreat to her chamber. (The title alludes to Prime Minister David Cameron telling a female MP to “Calm down, dear!”, which earned wide-spread criticism as a “classic sexist put-down”.) Three years later, Beard gave a second lecture for the same partners, entitled “Women in Power”, from Medusa to Merkel. It considered the extent to which the exclusion of women from power is culturally embedded, and how idioms from ancient Greece are still used to normalise gendered violence. She argues that “we don’t have a model or a template for what a powerful woman looks like. We only have templates that make them men.”

In August 2014, Beard was one of 200 public figures who were signatories to a letter to The Guardian expressing their hope that Scotland would vote to remain part of the United Kingdom in September’s referendum on that issue. In July 2015, Beard endorsed Jeremy Corbyn’s campaign in the Labour Party leadership election. She said: “If I were a member of the Labour Party, I would vote for Corbyn. He actually seems to have some ideological commitment, which could get the Labour Party to think about what it actually stands for.” For the 12 December 2019 general election, she was a proposer for the successful Cambridge Labour candidate Daniel Zeichner.

In December 2015, Beard was again a panellist on BBC’s Question Time from Bath. During the programme, she praised Labour Party leader Jeremy Corbyn for behaving with a “considerable degree of dignity” against claims he faces an overly hostile media. She said: “Quite a lot of what Corbyn says I agree with, and I rather like his different style of leadership. I like hearing argument not soundbites. If the Labour Party is going through a rough time, and I’m sure it is rough to be in there, it might actually all be to the good. He might be changing the party in a way that would make it easier for people like me to vote for.”

2016 saw Beard present Pompeii: New Secrets Revealed with Mary Beard on BBC One in March. While May 2016, brought about a four-part series shown on BBC Two, titled Mary Beard’s Ultimate Rome: Empire Without Limit.

In 2017, Beard became the target of considerable online abuse after she made the case that Roman Britain was more ethnically diverse than is often assumed. The source of the controversy was a BBC educational video depicting a senior Roman soldier as a black man, which Beard defended as entirely possible after the video received backlash. There followed, according to Beard, “a torrent of aggressive insults, on everything from my historical competence and elitist ivory tower viewpoint to my age, shape and gender [batty old broad, obese, etc etc].”

Beard’s standalone documentary Julius Caesar Revealed was shown on BBC One in February 2018. In March, she wrote and presented “How Do We Look?” and “The Eye of Faith”, two of the nine episodes in Civilisations, a reboot of the 1969 series by Kenneth Clark.

On 5 January 2019 Beard gave the sesquicentennial Public Lecture for the Society for Classical Studies, marking the 150-year anniversary of the organisation. The topic of her presentation was “What do we mean by Classics now?”.

She delivered the Gifford Lectures in May 2019 at Edinburgh University, under the title ‘The Ancient World and Us: From Fear and Loathing to Enlightenment and Ethics’.

In 2019, Beard appeared in an episode of The Grand Tour having dinner with host James May in an effort to get his car photographed by Paparazzi.