Facts: - caption: admiral -rrb- john markham -lrb- thomas lawrence , ca. 1793 - battles: american of cape henry french revolutionary wars action of 10 revolutionary april 1795 napoleonic wars war siege of charleston battle - death date: 13 february 1827 - allegiance: united kingdom united kingdom - rank: admiral - birth date: 13 june 1761 - serviceyears: 1775 & ndash ; 1826 - name: john markham - branch: 22px royal navy - laterwork: mp for portsmouth - image: admiral -rrb- . jpg john markham , by thomas lawrence -lrb- 1769-1830 - death place: naples - birth place: westminster Based on these bullet points, write a short biography describing the life of john markham -lrb- royal navy officer -rrb- .
The answer to this question is:
admiral john markham , -lrb- 13 june 1761 -- 13 february 1827 -rrb- was a royal navy officer of the late eighteenth and nineteenth centuries who is best known for his service at the admiralty as a supporter of earl st vincent and later as mp for portsmouth .