Mallinson is best known for writing a series of novels chronicling the (fictional) life of Matthew Hervey, an officer serving in the (fictional) British 6th Light Dragoons from the late Napoleonic Wars through subsequent colonial conflicts in India, North America and South Africa.
Mallinson took a break from his theological studies to join the Army in 1969, joining the King's Own Royal Border Regiment as a Second Lieutenant on probation, and served with the infantry in Cyprus, Malaysia, Northern Ireland and Germany. He was confirmed as a Second Lieutenant in 1970, promoted to Lieutenant on 11 February 1971, and promoted to Captain on 11 August 1975, and acting Major on 1 September 1979..
He transferred to the 13th/18th Royal Hussars (Queen Mary's Own) on 28 October 1980, and was promoted to substantive Major on 30 September 1981. He served in Whitehall, Norway, Cyprus and again in Germany. He was promoted to Lieutenant Colonel on 31 December 1988 (with seniority from 30 June 1988), commanding his Regiment from 1988 to 1991. He was promoted to acting Colonel on 1 December 1992, and to substantive rank on 30 June 1993 and then to Brigadier on 1 September 1999.
The Hervey novels are similar to the Sharpe novels written by Bernard Cornwell in that the heroes of both series of novels are British Army officers. Hervey (a cavalry officer), however, is a "proper" officer, unlike Sharpe (an infantry officer), who was raised from the ranks. Sharpe's campaigning was largely confined to the Napoleonic Wars, with some pre-Napoleonic India experience, whilst Hervey campaigned for many years afterwards in Canada, India, South Africa, Burma and the Balkans.
In UK hardback publication order, the Hervey novels are:
- A Close Run Thing (1999): Cornet Hervey's adventures before and during the Battle of Waterloo.
- The Nizam's Daughters (2000): Hervey in India, defending the fictional princely state of Chintal (published in the US as Honourable Company).
- A Regimental Affair (2001): problems in the regiment in England and Canada.
- A Call to Arms (2002): back in India, an independent excursion on the borders of Burma.
- The Sabre's Edge (2003): set in the First Burmese War in 1824, and the siege of Bharatpur in 1826.
- Rumours of War (2004): Hervey in Portugal in 1826, with flashbacks to the Peninsular War before the battle of Corunna in 1809.
- An Act of Courage (2005): Hervey imprisoned at Badajoz at Christmas 1826, with further flashbacks to the Battle of Talavera in 1809 and the Siege of Badajoz in 1812.
- Company of Spears (2006): Hervey in the Cape Colony in 1827 fighting the Zulus, immediately before the death of Shaka and the accession of Dingane.
- Man of War (2007): in 1827, Matthew Hervey is in England; unusually seeing no action. Meanwhile in a parallel story line, his old friend Peto takes part in the Battle of Navarino.
- Warrior (2008): 1828 – Hervey is tasked with escorting an embassy to Shaka, King of the Zulus, whose motives are under suspicion.
- On His Majesty's Service (2011): Hervey is sent as an observer to the Russian army during their war with the Ottoman Empire in 1829.
- Words of Command (due March 2015)
- Light Dragoons (1993) – a non-fictional history of the four light cavalry regiments of the British Army. It was published in 1993, soon after he relinquished command of 13th/18th Royal Hussars (which includes (in merged form) two of the light dragoon regiments: the 13th was originally raised as a heavy dragoon regiment in 1715 but later converted to light dragoons; the 18th was raised as a light dragoon regiment in 1759; both retitled as hussars in 1861, merged in 1922 and then merged with the 15th/19th The King's Royal Hussars to form the present Light Dragoons in 1992).
- The Making of the British Army: From the English Civil War to the War On Terror (2009). The book examines nearly 500 years of the British Army and examines how its military actions has made it one of the most effective fighting forces in the world today. Mallinson demonstrates how people and events have shaped the army's development. Sections include: how Marlborough's victory at Blenheim is linked to Wellington's success at Waterloo; how the desperate fight at Rorke's Drift in 1879 underpinned the heroism of the airborne forces in Arnhem in 1944; and why Montgomery's momentous victory at El Alamein mattered long after the Second World War.
- 1914: Fight the Good Fight: Britain, the Army and the Coming of the First World War (2013) - In this major new history, one of Britain's foremost military historians and defence experts tackles the origins - and the opening first few weeks of fighting - of what would become known as 'the war to end all wars'. Intensely researched and convincingly argued, Allan Mallinson explores and explains the grand strategic shift that occurred in the century before the war, the British Army's regeneration after its drubbings in its fight against the Boer in South Africa, its almost calamitous experience of the first twenty days' fighting in Flanders to the point at which the British Expeditionary Force - the 'Old Contemptibles' - took up the pick and the spade in the middle of September 1914. For it was then that the war changed from one of rapid and brutal movement into the now familiar image of the trenches and the coming of the Territorials, Kitchener's 'Pals', and ultimately the conscripts - and of course the poets. And with them, that terrible sense of the pity and of the futility.
- "MALLINSON, Allan Lawrence". Who's Who 2014. A & C Black. November 2014. Retrieved 6 February 2015.
- The London Gazette: . 23 September 1969. Retrieved 17 April 2008.
- The London Gazette: . 13 February 1970. Retrieved 17 April 2008.
- The London Gazette: . 12 February 1971. Retrieved 17 April 2008.
- The London Gazette: . 12 August 1975. Retrieved 17 April 2008.
- The London Gazette: . 24 November 1980. Retrieved 17 April 2008.
- The London Gazette: . 19 October 1981. Retrieved 17 April 2008.
- The London Gazette: . 9 January 1989. Retrieved 17 April 2008.
- The London Gazette: . 5 July 1993. Retrieved 17 April 2008.
- The London Gazette: . 23 March 2004. Retrieved 17 April 2008.
- "Allan Mallinson biblio". FantasticFiction. Retrieved 20 February 2008.