In 1902, at the age of 25 and together with his cousin Gustav August Ficker, Ernst Heinrich Roth started his own violin-making business, where over the years he worked in conjunction with apprentices, many of whom went on to become well-known violin makers in their own right. The exact extent of Ernst Heinrich Roth's involvement in the making of his instruments has long been a topic for debate, but it is now generally believed that the best instruments were made mainly by Roth himself. The instruments of the Ernst Heinrich Roth workshop were soon in demand all over Europe.