In the 14th century, before being declared as a town, Rauma had a Franciscan monastery and a Catholic church. In 1550, the townsmen of Rauma were ordered to relocate to Helsinki, but this was successfully countered and Rauma could continue its growth.
Practically the whole wooden town of Rauma was devastated in the fires of 1640 and 1682. The wooden city centre, which is how large the town was until 1809, has approximately 600 wooden buildings. The neo-renaissance style of many of the houses is a result of prosperity brought on by seafaring. In 1897 Rauma had the largest fleet of sailing boats in Finland, totalling 57 vessels. Goods were mainly exported to Germany, Stockholm and the Baltic states. In the 1890s, Rauma got a teacher's college (a 'seminar'), which was later annexed to the University of Turku. The department of education still exists in Rauma.
After the second world war, Rauma developed into an industrial city, the main industries being shipbuilding, paper and pulp mills, and metal industry. Rauma is also the fifth largest port in Finland with almost six million tonnes of shipping per year.
Rauma has its own dialect of Finnish, which the locals think of as an actual language. The dialect inherits words from languages such as Swedish and English due to the seafaring past. The dialect has been diluted into mainstream Finnish in day-to-day use, but it is fairly well studied (mainly by Hj. Nortamo) and practiced as a hobby. Rauma and the surrounding municipality of Rauman maalaiskunta ("rural municipality of Rauma") were merged in 1993.