Ian Kershaw, Hitler: 1936-1945 Nemesis.On 7 September Hitler had been ready to negotitate with the Poles, recognizing a rump Polish state (with territorial concessions to Germany and breaking of ties with Britain and France), together with an independent western Ukraine. Five days later he still favoured a quasi-autonomous Polish rump state with which he could negotiate a peace in the east, and thought of limiting territorial demands to Upper Silesia and the Corridor if the West stayed out. Another option advanced by Ribbentrop was a division between Germany and Russia, and the creation, out of the rump of Poland, of an autonomous Galician and Polish Ukraine - a proposal unlikely to commend itself to Moscow. The belated Soviet occupation of eastern Poland on 17 September in any case promptly ruled out this possibility. Hitler still left open the final shape of Poland in his Danzig speech on 19 September. During the next days, Stalin made plain his opposition to the existence of a Polish rump state. His initial preference for the demarcation line along the line of the Pissia, Narev, Vistula, and San rivers was then replaced by the proposal to exchange central Polish territories within the Soviet zone between the Vistula and Bug rivers for Lithuania. Once Hitler had accepted this proposal - the basis of the German-Soviet Treaty of Friendship signed on 28 September 1939 - the question of whether or not there would be a ands rump state was in Berlin's hands alone.
Hitler was still contemplating the possibility of some form of Polish political entity at the end of the month. He held out the prospect of re-creating a truncated Polish state - though expressly ruling out any re-creation of the Poland of the Versailles settlement - for the last time in his Reichstag speech of 6 October, as part of his 'peace offer' to the West. But by then the provisional arrnagements set up to administer occupied Poland had in effect already eliminated what remained of such a prospect. Even before the formality of Chamberlain's rejection of the 'peace offer' on 12 October, they had created their own dynamic militating towards a rump Polish territory - the 'General Government', as it came to be known - alongside the substantial parts of the former Polish state to be incorporated in the Reich itself.
Brendan Simms, Hitler: Only the World Was Enough, pages 355-356.That said, Hitler kept his options open in Poland for at least six weeks after the invasion began, partly in the residual hope of securing its assistance against the Soviet Union, but mainly in order to facilitate an agreement with London. In his remarks to Halder shortly after the British declaration of war, he held out the possibility that ‘rump Poland’ would be ‘recognized’, adding that while Germany would control the Narew and the Warsaw industrial area, ‘Krakau, Polen’ and ‘Ukraine’ would be ‘independent’. A month into the invasion, Hitler was still considering options for Poland, one of which was a ‘rump state’. This suggests that Hitler had not given up his idea of a modus vivendi with Poland based on joint expansion eastwards. A certain residual respect for Poland, even after the invasion, was evident in the fact that Hitler praised Marshal Piłsudski as ‘a man of indisputable realist understanding and energy’ in his Danzig speech of 19 September, blaming his death for the renewed hostility between Germany and Poland. The Führer also ordered an honour guard to be placed outside Marshal Piłsudski’s final resting place in Cracow, where it remained throughout the entire German occupation.
These moves culminated in a dramatic Reichstag address on 6 October 1939, in which Hitler announced victory in Poland and offered Britain a peace settlement which would include an ill-defined rump Polish statehood. This offer was not merely tactically motivated but–by his own lights–sincerely meant. Failure to accept the proffered hand, he warned, would lead to the destruction of the British Empire. ‘This annihilatory struggle,’ Hitler proclaimed, ‘will not be limited to the mainland [of Europe]. No. It will spread far across the sea. There are no more islands today.’
Jeremy Noakes, Nazism, 1919-1945: Foreign policy, war and racial extermination, page 315.At an interview with Ciano on 1 October, Hitler gave the impression that he was prepared to allow a Polish rump state to exist as a satellite of Germany
As we all know, Hitler was quite good at saying the right thing at the right time to get his own way e.g. he claimed that the Sudetenland was his last territorial demand in Europe. But, was there any truth in Hitler's thoughts about a Polish rump state?