Later in the year, Maximian led a surprise invasion of the Agri Decumates - a region between the upper Rhine and upper Danube deep within Alamanni territory - while Diocletian invaded Germany via Raetia.
Maximian allowed a settlement of Frisii, Salian Franks, Chamavi and other tribes along a strip of Roman territory, either between the Rhine and Waal rivers from Noviomagus (Nijmegen, Netherlands) to Traiectum, (Utrecht, Netherlands)[REF] or near Trier [REF].