1980–1990

Bradshaw's first published novels were the Arthurian historical fantasy trilogy, Down the Long Wind. These three young adult books — Hawk of May, Kingdom of Summer, and In Winter's Shadow — were released between 1980 and 1982. Set in Sub-Roman Britain, the trilogy's main character is Gwalchmai (Gawain), who must choose between supporting his evil mother Morgawse or his maternal uncle King Arthur. The title Down the Long Wind is taken from Alfred, Lord Tennyson's Idylls of the King:

"And fainter onward, like wild birds that change

Their season in the night and wail their way

From cloud to cloud, down the long wind the dream

Shrilled; but in going mingled

with dim cries."

Bradshaw next began writing adult historical fiction. Her 1986 novel, The Beacon at Alexandria, features Charis of Ephesus, a female doctor cross-dressing as a eunuch in 4th century Alexandria, in Roman Egypt.

The Bearkeeper's Daughter tells the story of Theodora, empress consort of Byzantine Emperor Justinian I. Theodora was born into the lowest class of Byzantine society, and was the daughter of Acacius, a bearkeeper for the circus.

Imperial Purple (UK title: The Colour of Power), released in 1988, features Demetrias of Tyre, a woman who was born into slavery but who is becoming a skilled weaver. The plot focuses on her discovery of a plot to depose Theodosius II and remove from power his sister Pulcheria.

In 1990 Bradshaw wrote Horses of Heaven, about a marriage alliance between the Saka Kingdom of Ferghana and the Greco-Bactrian Kingdom. The marriage of King Mauakes and Princess Heliokleia occurs around 140 BC, and brings many changes at court.

1991–2000

Bradshaw next turned to writing three children's books — starting with two linked tales involving Ancient Egypt, The Dragon and the Thief in 1991 and The Land of Gold in 1992. The latter features a Nubian princess who survives her parents' murder, and attempts to regain her throne with the assistance of the dragon Hathor.

These two books were followed by Beyond the North Wind (1993). The novel features a young magician assigned by Apollo to protect a tribe of griffins from a hostile queen. The title is again a reference to an earlier work, in this that of case Aristeas of Proconnesus, a 7th-century BC Greek, who reported that the griffins lived in Scythia, near the cave of Boreas, the North Wind. The Dragon and the Thief, The Land of Gold, and Beyond the North Wind all began as stories for the pleasure of her own children.

Bradshaw then continued her works of serious adult historical fiction with Island of Ghosts in 1998. The novel tells the story of Ariantes, one of 8,000 Sarmatians in military service to Marcus Aurelius.

In 2000 she wrote her first science fiction novel, The Wrong Reflection, about an amnesiac who finds his given identity of "Paul Anderson" to be a fabrication.

This was followed by historical novel The Sand-Reckoner, a telling of the story of Archimedes of Syracuse, Italy, from his studies at the Library of Alexandria to his involvement in the Second Punic War (218 – 202 BC).

2001–present

In 2001, Bradshaw published her second science fiction novel, Dangerous Notes. It features Valeria Thornham, a young classical guitarist and composer whose brain was implanted with cloned stem cells in childhood after an accident. She is considered a potential psychotic and is arrested and detained at a mental research facility, where she is threatened with the prospect of undergoing surgery to remove the part of her brain that is responsible for her extraordinary musical talent.

Bradshaw's 2001 historical novel The Wolf Hunt was based on Marie de France's Breton lai Bisclavret, and features Marie Penthive of Chalendrey, a Norman kidnapped and taken to the Duchy of Brittany. Marie then becomes involved in the life of the late 11th-century Duchy's court and its plots.

Her next historical novel, Cleopatra's Heir (2002) tells the tale of Caesarion, son of Julius Caesar and Cleopatra VII of Egypt, who managed to escape execution at the order of his adoptive brother Caesar Augustus. The young man is then forced in a life of poverty in his new environment, the Roman Empire.

In 2002 Bradshaw also wrote a short story set in Ancient Egypt, The Justice of Isis, taking place in Alexandria in 58 BCE, during the reign of Ptolemy XII. It was published in The Mammoth Book of Egyptian Whodunits. This short story was also published in Czech as Esetina spravedlnost in 2004.

This was followed by another historical novel, Render Unto Caesar (2003), featuring Hermogenes, a Roman citizen of Greek origin, meeting prejudice in the city of Rome when he tries to collect a debt, and his body guard, "Cantabra", a former gladiatrix, originally from Cantabria.

In 2003, Bradshaw also wrote a short story set in the last decades of Imperial Rome, The Malice of the Anicii. Written in the style of a scholarly edition of Ammianus Marcellinus's History of Rome, the story was published in The Mammoth Book of Roman Whodunits.

Bradshaw returned to science fiction with The Somers Treatment (2003). The novel features neurosurgeon David Somers advancing his own unique treatment of specific language impairment. However, his research receives its funding from MI5, for reasons that remain secret to the public.

Her 2004 historical novel The Alchemy of Fire takes place in Constantinople under Constantine IV. Anna, former concubine to a prince of the Heraclian Dynasty, attempts to raise her daughter Theodosia on her own while protecting the secret of the girl's noble birth. Meanwhile, alchemist Kallinikos of Baalbek works in creating Greek fire.

The Elixir of Youth (2006) was Bradshaw's next novel, looking at the complex relationship between a philosopher daughter and her molecular biologist father, who walked out of the family when she was a child, and whose serum to repair the effects of aging on the skin has gone missing. Like her earlier novel Dangerous Notes (2001), the use of stem cells in research is a theme.

Bloodwood was published in 2007. This novel is set in contemporary Britain, and focuses on Antonia Lanchester, a terminally ill employee of a home-furnishing company, who hands over incriminating files about illegal logging and corruption from her employer's computer to an environmental campaign group.

Her next novel, Dark North (2007), was a return to Roman Britain for Bradshaw. Set in 208 CE, it looks at the troubled reign of Emperor Septimius Severus — and his attempt to conquer Scotland — through the eyes of Memnon (an African cavalry scout) and members of Empress Julia Domna's household.

The Sun's Bride (2008) is set in Ancient Greece, in Rhodes in the year 246 BCE. Shipping, piracy and the politics of the eastern Mediterranean Sea are the well-researched backdrop to the story of two people caught up in the end of the reign of Antiochus II Theos and the beginning of the Third Syrian War, and how these change their lives.

London in Chains (2009) is her first historical novel of a planned two set in the English Civil War. Like many of her novels, it focuses on one woman's struggle for independence in a male dominated world. Starting in 1647, it is set around a Lucy Wentor, a young woman establishing herself in the politically sensitive publishing trade in London.

A Corruptible Crown (2011) follows Lucy's career in publishing: printing news-books and avoiding censors.