Having joined the army in 1787, he served with the 60th Regiment of Foot in the West Indies, fighting at the start of the French Revolutionary Wars in the Battle of Martinique and Invasion of Guadeloupe, being severely wounded in the latter.

Rebow spent some time at Lisbon before returning home in January 1813; he received no further military commands but by seniority was promoted to general in 1841.

Slater, in command of the battalion's Grenadier Company, took part in the British expedition that set out to capture French island possessions there.

[1][4] Slater fought at the successful Battle of Martinique between February and March 1794, and on 1 April was present at the capture of Saint Lucia.

[1][4][6] In England Slater purchased his promotion to major, staying in the 60th, on 20 February and then on 22 March married Mary Hester Rebow (died 1834) in St Margaret's, Westminster.

[1][4] Part of the Household Cavalry Brigade, the 2nd Life Guards were a predominantly ceremonial regiment that had last seen active service half a century before at the Battle of Fontenoy in 1745.

The mistake was recognised by the War Office on 25 September that year and Rebow's rank was corrected, listing him as a major and lieutenant-colonel with seniority from 1799.

[11][13][14] Rebow subsequently requested a leave of absence in mid-January 1813; he returned to England and received no further military duties, retiring to live at Wivenhoe Park.

[1][10] Rebow died at Wivenhoe Park on 7 October 1845, aged 75, having had what military historians Ron McGuigan and Robert Burnham describe as an "unremarkable career".

Both were complete by 17 September; the money from the commissions, as Rebow had intended, allowed Constable to marry his long-time sweetheart Maria Bicknell.

[19] Rebow is described by art historians Leslie Parris and Ian Fleming-Williams as a more sympathetic patron of Constable than others such as Richard Benyon De Beauvoir.