Hungary is just a bit too far from the sea to have received very much attention from us. Nevertheless, armed Brits have conducted operations there.
For instance, in the late seventeenth century, assorted volunteers from Britain, including the son of Prince Rupert, fought in the army of Prince Eugene of Savoy as it pushed the Ottomans back through Hungary. Buda was stormed in 1686 and in 1687 the prince won a battle at Mohacs, scene of the decisive Ottoman victory in 1526.
The RAF operated over Hungary in the Second World War. SOE also operated in Hungary, though not extensively. SOE had difficulty establishing a presence in the country, with a couple of failed missions. When Basil Davidson was working as liaison with the Yugoslav partisans, SOE sent him into Hungary to try to organise a rebel movement there, but he realised that it wasn’t going to work and eventually crossed back into the Fruska Gora area.