Germania Superior

The upper Rhine command, named for a river frontier rather than for Germany, and holding the only part of the line Rome pushed beyond. Superior meant upstream: the province ran along the Rhine from roughly Lake Constance to the Vinxtbach, with Mogontiacum, now Mainz, as its capital. It began as a military district under the governor of Belgica and was made a full province around 85. Its purpose was to hold the river with legions - two for most of its history - after Rome abandoned the attempt to conquer Germany beyond it. In the re-entrant angle between the upper Rhine and the Danube, Rome did advance, taking the Agri Decumates and fortifying it with the Limes Germanicus, a line of palisade, ditch, towers and forts running some 550 kilometres and now a World Heritage site. It is the longest ancient monument in Europe after Hadrian's Wall. The province was heavily militarised and its economy shaped by supplying the army, which is why the Rhine cities grew where they did. Vineyards were planted along the Rhine and Moselle under Roman rule. Aquae Mattiacorum, now Wiesbaden, and Aquae, now Baden-Baden, were spa towns. The Agri Decumates were given up around 260 under pressure from the Alamanni. The frontier fell back to the Rhine and held for another century and a half. Mainz sits at the confluence of the Rhine and the Main. The province held around 40 forts along the limes at its height. Its legions proclaimed rival emperors more than once. Roman Trier and the Rhine cities remain major German centres today.

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