Thank you to Rex Brain for this:

On the island of Zakyinthos (also known as Zante), a small island off the west coast of Greece, an English Cemetery exists in the main town (Zakyinthos). This island was under British rule some time around the late 1700 early 1800s. This headstone was located in the cemetery.

The inscription reads : THE / 90. LIGHT INFANTRY / TO THEIR ESTEEMED AND LAMENTED /ADJUTANT / LIEUT HECTOR MUNROE / WHO DIED ON THE 3. AUG 1828 / AGED 34.YEARS