I have already presented one of the badges of the 54th Infantry Regiment in connection with the city of Olomouc: https://kappenabzeichen.hu/en/olmutz/ The regiment with the 5th Infantry division was deployed mainly on the Russian front. Its staff consisted of soldiers of German and Czech (Moravian) nationality.
Another, more common badge of the regiment is shown in this post. The slogan of the regiment can also be read on this: “Drzte se Hanaci!” that is, “Stick to the roots!”. In this post, in addition to the badge, I also present a letter seal decorated with a portrait of the regiment’s owner. Count Starhemberg was a successful Austrian warlord in the second half of the 1600s. He was one of the protagonists of the fighting against the Turks at the time. During the second Turkish siege of Vienna in 1863, he was the city commander. He then took part in the recapture of Buda in 1686 in the rank of general. From 1691 he was president of the Vienna Military Council.
Based on all this, I think it was not a surprising or even deserved gesture to honor his name with the ownership of an infantry regiment. I don’t know why the 54th Regiment was chosen. There are also two streets in Vienna named after the general.