Around 1470-1500 shields started to become less common because of a combination of things. Plate armor started to become cheaper. People in plate armor don't need shields to protect themself against missile fire and people fighting against plate armor need something big and often two handed to penetrate the plate armor. At the same time combat moved towards pike and shot formations that had less use for shields. Some lighter troops might have keept shields, but for the most part people started to use the smaller bucklers. They didn't give the same protection against missile fire, but where easier to parry with and for a small amount of time the spanish used people armed with swords and bucklers to try and break pike deadlocks. These troops also feel out of favour and around 1530 we stop seeing them on major battle fields.

They continued to be used in smaller skirmishes betwen nobles, gangs and scotsmen until the 18th century.