Numerous carved tombstones have been found in Govan Old Churchyard include five hogbacked, carved tombstones,which reflect Viking influence, and an elaborately carved stone coffin known as The Govan Sarcophagus. The stones can be seen inside the Victorian Gothic Revival church (1883-8 by Robert Rowand Anderson).
Over the last 150 years 47 carved stones have been recorded at Govan, of which 31 survive today, all now protected within the church. They date from the 9th to 11th century. They were found within the churchyard which was once surrounded by a bank and ditch. The evidence of excavations indicates that this was an early Christian site going back to the 5th or 6th century AD. There have been several previous churches here but only traces of the foundations seem to remain from the medieval church which was demolished in 1762. However, beneath these foundations archaeologists found signs of still earlier burials.
Nearby, though it has now been levelled, was a mound known as the Doomster Hill, probably used as a ceremonial gathering place. It indicates the importance of Govan in the early medieval period. It has been suggested that this could have been a royal graveyard associated with the kingdom of Strathclyde the centre of which was at Dumbarton.
The most ornate carving of a horseman, animals and interlace patterns, is on the sandstone tomb known as The Govan Sarcophagus and associated (though it cannot be proved) with the original dedicatee of the church, St Constantine who may have been the Scottish king Constantine, son of Kenneth, who ruled from 862-878. It is the only sarcophagus carved from solid stone known from pre-Norman north Britain. There are also individual carved crosses and cross slabs. The most remarkable monuments are five hogback gravestones, carved with roof tiles and with stylised animal end pieces. These date from the mid to late 10th century and are the largest group known anywhere in Britain. They are all associated with areas of strong Viking influence, probably through trade and perhaps settlement along the Clyde.