The Chinese invented a sauce called ‘ke-tsiap’, spelled K-E-hyphen-T-S-I-A-P in the 1690s. It was made from fish and spices, but abolutely no tomatoes.
By the early eighteenth century, its popularity had spread to Malaysia, and this is where British explorers first found it and liked it.
By 1740 the sauce was part of the English diet-people were eating a lot of it and it was also becoming popular in the American colonies.
They renamed the sauce “ketchup”, because it was a bit easier for the English to pronounce. Then about fiflty years later, in 1790, some American colonists in New England mixed tomatoes into the sauce and it became known as ‘tomato ketchup’.