Gendall was employed as a servant but his drawings were talent spotted by an employee of the print seller Rudolf Ackermann in a shop owned by W.

[1] Ackermann arranged to bring Gendall to London where he initially worked filing artists images.

[2] On 19 January 1824 he married the widow of fellow artist Daniel Havell (1785-1822), Maria Alice Havell (née Wilmot) (1796-1873), daughter of Dr. Samuel & Martha (née Russell) Wilmot at St Martin-in-the-Fields on Trafalgar Square.

[1] Gendall's reputation enabled him to launch an art school that attracted Richard Ford, who was a writer, and local Edward Bowring Stephens, who became a sculptor,[1] besides sculptor William John Seward Webber.,[5] 1854 saw the establishment of Exeter University, and in 1861 Gendall was very involved with creation of a museum for Exeter.

His former pupil Edward Bowring Stephens launched an unsuccessful campaign to buy some of his work for Exeter,[7] but the museum has since made purchases.