General Sir William Green, 1st Baronet FRS (4 April 1725 – 10 January 1811) was a British Army officer, of Marass, Kent.

Following his return to England, Green was named senior engineer for Gibraltar about 1761, and the next year promoted to lieutenant colonel.

He was promoted to chief engineer for Gibraltar in 1770, and designed and executed a number of military works on the Rock.

[3] His mother was the sister of Adam Smith (1723–1790), author of The Theory of Moral Sentiments and An Inquiry into the Nature and Causes of the Wealth of Nations.

His wife was also the granddaughter of Colonel Jonas Watson (1663–1741), who led the Royal Artillery at the Siege of Carthagena, where he died.

His son, an officer who attained the rank of colonel, attended Prince Edward, later the Duke of Kent, in his travels, and died unmarried, without issue.

Plans that he and another officer drew up of the tunnels and caves of the fortress of Luxemburg, and of the area between Bois-le-Duc and Geertruidenberg, are held by the British Museum.

Green returned to England in 1769 to present his suggestions for improving the defence of Gibraltar to the Board of Ordnance.

General Skinner, the chief engineer of Great Britain, supported the expenditures necessary for Green's military works, which were then undertaken.

The situation induced Lieutenant Colonel William Green to suggest the creation of a company of military artificers, a regiment of trained artisans.

[12][13][14] In 1777, Green was promoted to colonel, after which he was sent by Governor George Augustus Eliott to England to request additional funds to further improve the military works at Gibraltar.

His meetings included several with the king and he returned to Gibraltar the following year, authorised to proceed with the new works.

[3][8] On 18 July 1781, the Queen's Battery at Willis's Plateau sustained severe damage from enemy fire.

On 13 September 1782, with Gibraltar under attack from both land and naval forces, his kilns maintained a continuous supply of red hot shot.

[16] General Sir William Green died on 10 January 1811 at Bifrons, near Canterbury, Kent, although his date of death has also been given as February 1811.

[3][2] His son, Colonel Sir Justly Watson Green, 2nd Baronet of Marass, Kent, succeeded to the baronetcy, became extinct upon his death.

[3][7] Green is one of the officers depicted in The Defeat of the Floating Batteries at Gibraltar, September 1782 (pictured above) by John Singleton Copley (1738–1815).

[18] A portrait of Green, oil on canvas, that was executed circa 1785, is held by the Convent, the residence of the Governor of Gibraltar.

[23] In addition, Green's Lodge Nature Trail extends off Signal Station Road in northern Gibraltar.