When in June 1922 the Polish army was entering Katowice, the state border cut through one of the largest industrial districts in Europe. Mines, steelworks, water supply systems and power lines that until then had worked as one organism suddenly found themselves on two sides of the border. To avoid cutting it up in a way that would halt the economic life of the region, Poland and Germany signed an agreement running to hundreds of articles: the Geneva Convention on Upper Silesia.

Where the border came from

The plebiscite of 20 March 1921 did not settle the dispute. About 60 per cent of the nearly 1.2 million voters declared for the region remaining in Germany, and the Powers could not agree for a long time on a division. The third Silesian uprising of May 1921 was meant to force a solution more favourable to Poland. In the end the matter was passed to the Council of the League of Nations, which in October 1921 issued a verdict on partition, approved by the Conference of Ambassadors.

Poland received 29 per cent of the area of the disputed territory and 46 per cent of its population. Poland gained Katowice, Królewska Huta (today's Chorzów), Pszczyna, Rybnik, Mysłowice, Mikołów, Żory and Tarnowskie Góry, while Bytom, Zabrze, Gliwice, Racibórz and Opole, among others, remained in Germany. Of a total of 91 mines, 72 ended up in the Polish state, and of 27 steelworks, 23.

The entry of the troops on 20 June 1922

The takeover of the territory followed a set order. Polish units crossed the former border near Szopienice on 20 June 1922 and marched through Burowiec and Zawodzie to Katowice, where they were welcomed by crowds and several dozen triumphal arches. The occupation of the areas assigned to Poland lasted until 4 July. The Inter-Allied Commission handed over power on 14 July, and the next day the new border acquired legal force. Marking it out on the ground was completed only in 1923, because it ran across a built-up, strongly integrated industrial basin.

What the convention regulated

The convention was signed in Geneva on 15 May 1922 and ratified by an act of 24 May. The document had 606 articles and was concluded for 15 years. It was to protect the Upper Silesian market, which had until then been a single industrial organism, and to guarantee the civil and citizens' rights of the inhabitants on both sides of the border. It therefore dealt with two large matters at once: the economy and the protection of national minorities, German in Poland and Polish in Germany.

The scale of the problem was practical. The border separated the mines and plants of a single concern, suppliers from customers, and also sources of supply and financing. The water supply system, the power grid and the gas network were cut. The convention was to set rules of cooperation across the border so that the day-to-day functioning of these networks and enterprises did not depend on the goodwill of one of the parties.

Who settled disputes

The convention established two international institutions. The first was the Upper Silesian Mixed Commission, based in Katowice and headed by the Swiss Felix Calonder, hence the colloquial name Calonder's Tribunal. The second was the Arbitral Tribunal for Upper Silesia, based in Bytom, and thus on the German side of the border. It was headed by the Belgian Georges Kaeckenbeeck, appointed by the Council of the League of Nations. Its membership also included one Polish and one German judge. The presidents of both institutions could be neither Poles nor Germans: disputes between the states were to be decided by someone from outside them.

Life of people on both sides

Inhabitants could make use of the option, that is, the choice of citizenship and country of residence. Daily crossing of the border for work or private matters was eased by circulation cards. It is estimated that in 1922-1924 about 170,000 Upper Silesians, almost 20 per cent of the permanent residents entitled to vote in the plebiscite, moved to the other side of the border, and more than 100,000 of them were Germans leaving Poland. Despite the border Polish-German marriages, mixed workplaces and religious communities continued to exist.

The protection of minorities worked unevenly in practice. According to one assessment both states applied discriminatory measures against minorities, although on the German side they were said to be considerably harsher. This is one voice in a dispute that looked different on each side of the border.

The end of the convention

The convention remained in force until 1937. German newspapers used its expiry for an anti-Polish propaganda campaign. The protection of minorities was replaced by a joint Polish-German declaration, which remained in force until Germany's attack on Poland on 1 September 1939. The autonomous Silesian Voivodeship, which we cover in a separate text on the Silesian Sejm, thus existed throughout this time in the shadow of an agreement that organised its relations with its neighbour.