Throughout the French Revolutionary and Napoleonic Wars, a complex system of alliances and counter-alliances were used to maintain the balance of power in Europe. Napoleon himself did his utmost to stir up discontent amongst those nations which remained neutral and one of his more conspicuous successes was the formation of the so-called "Armed Neutrality" of Russia, Denmark, Sweden and Prussia towards the end of 1800. The immediate result of this hostile coalition was the closure of the Baltic which, with its vital supplies of timber, tar and other naval war materials, was something Britain could not allow to continue any longer than was necessary. In the hope that Denmark -- guardian of The Sound and thus entry into the Baltic Sea -- would prefer negotiation to war, the British government sent its envoy, the Honourable Nicholas Vansittart (see note below), to Copenhagen aboard the 32-gun frigate H.M.S. Blanche. Two weeks later, on 12th March 1801, a fleet under Admiral Sir Hyde Parker, with Nelson as his second-in-command, sailed from Yarmouth Roads bound for Denmark where, it was believed, this show of force would have the required effect on the discussions. After a particularly stormy passage, the fleet eventually reached the Naze of Norway where it was joined, on 23rd March, by H.M.S. Blanche. Aboard was Mr. Vansittart who reported that not only had his offers of reconciliation been rebuffed, but that Denmark was openly defiant towards Great Britain. One week later, on 2nd April, Nelson's daring carried the day at the Battle of Copenhagen where he won the second of his great victories despite Parker's signal to break off the action which Nelson chose to ignore through the celebrated ruse of placing his telescope to his 'blind' eye.
Although there is no evidence of any lasting friendship between Nelson and Vansittart, it seems likely that Nelson gave the envoy this box (dated 24th March 1801) as a memento not only of their meeting but, more importantly, in gratitude for the valuable strategic information Vansittart had supplied about the Danish fleet and its anchorage which then enabled Nelson to bring off such a notable victory.
The Honourable Nicholas Vansittart, later 1st Baron Bexley (1766-1851), served as an M.P. from 1796-1823, latterly for Harwich, and enjoyed a distinguished political career during which he was Secretary to the Treasury, 1801-04 and 1806-07, and Chancellor of the Exchequer from 1812 until 1823.