The best-known version of the grand-ducal coat of arms is found on the tomb of Gustavus I (1523–60) in the Uppsala cathedral ("Figure 5"). It has been suggested that either Duke John himself, or his brother Eric XIV, was leading the design work on the heraldic signs on the tomb. Neither statement can be confirmed, but it is known that Eric XIV showed an interest in heraldry. The monument was commissioned from Guillaume Boyen (Willem Boy), a Flemish architect and sculptor who had worked in Sweden. He started on the task in Antwerp in 1562, completing it 10 years later; however, the tomb was not in place in Uppsala until the early 1580s, and the finishing work lasted until 1591. In addition to the royal arms of Sweden and those of Finland, the arms of the 11 provinces are depicted. From Finland they include North and South Finland, as well as Tavastia and Karelia. The work of Willem Boy is of exceptional quality, which is perhaps explained by the fact that lions were a dominant feature in the heraldry of Flanders, and he would therefore have had a great deal of exposure to it before receiving the commission for the tomb of Gustavus I.