He commanded HMS Monarch at Copenhagen in 1801, for which he was mentioned in despatches but despite this and having served under some influential admirals, his promotion was slow and he never rose above the rank of captain.

[1] Yelland later transferred to HMS London, then carrying the flag of Admiral Thomas Graves in the waters around North America.

[2] Following the Treaty of Paris in September 1783, Yelland found himself on half pay and, apart from a short period aboard the fireship Tisiphone in 1790, remained so until war resumed in 1793.

Yelland failed to secure a position on any ship for the whole of 1797 but in January the following year, signed on as first lieutenant aboard HMS Veteran.

In March the ship led Admiral Hyde Parker's fleet through the sound between Denmark and Sweden,[3] before joining Horatio Nelson's squadron for the Battle of Copenhagen on 2 April.

[6] The latter writing, "I cannot close this without acquainting their Lordships, that Captain Mosse being killed very early in the Action, Lieutenant John Yelland continued it with the greatest Spirit and good Conduct; I must therefore, in Justice to his Merit, beg Leave to recommend him to their Lordships' Favour"[7] Parker could have promoted Yelland himself but chose instead to advance his own favourites.

[8] It was spotted at dawn on 24 April by a British squadron comprising the 38-gun HMS Leda, two sloops, eight gun-brigs and Fury, all of which, immediately gave chase.