You will surely have noticed that we have an affection for Mr Baedeker, the German publisher who in the nineteenth century did so much to encourage a new generation of independent travellers. Devotees of Baedeker's guidebooks set out from home to go in search of sublime vistas, agreeable wayside inns, picturesque curiosities and stellar attractions. The guidebooks were full of wise advice - how the traveller might decently react to courtesy or deceit, whether a gentleman might be wiser to offer French gold or English sovereigns in this or that canton of Switzerland, and where and when a passport might be advisable.
Curiously, in the nineteenth century, passports were not the sine qua non of European travel that they were to become after the First World War. The passport fad has waxed and waned through time. As passport free travel becomes more common in Europe today (at least between the countries that are party to the Schengen treaty), it may come as a surprise to some to find that, back in mid-nineteenth century, many travellers drifted around Europe without let or hindrance.
But that halcyon period of passport-free travel, a sort of precursor of the modern Schengen system, was not to last forever. In 1879 the government of a recently unified Germany imposed a passport and visa requirement on travellers arriving from Russia - including its own returning citizens. Ostensibly the measure was introduced to protect the Reich's citizens from disease, but events tell otherwise. The plague of early 1879 in parts of Russia was a short-lived affair but the passport requirement stuck for good.