The two units that I think intertwine the most with World War Two are World War One and Interwar Totalitarianism. This is because I believe those units are the two main causes of how the second world war started. After World War One, Japan, China, Italy, Germany and Russia were left in complete chaos. All countries were left in great debt, with no way to pay it off. Along with the economic instability, China had trouble with trade, Italy had no natural resources, and both Russia and Germany were in a state of extreme poverty and inflation. Consequently, because of all of the chaos left from WW1, the people of those countries were in despair. They craved a leader who could promise and fulfill beneficial change. Moreover, this is when Totalitarian Leaders stepped in and gained complete control.
Although the Totalitarian leaders stepped in and various changes were made, chaos involving the citizens arose. For example, the rights of the people decreased drastically and "[the leaders] scorned the democratic ideals of civil liberties, of the dignity the individual, and world peace, and they openly declared their intent to destroy democracy" (49). The citizens were no longer able to act for themselves, "If the state was a machine, its citizens were simply parts- parts that worked smoothly and quietly were oiled. Those that made noise were removed and discarded" (62). Therefore in spite of the citizen's rights decreasing, even more chaos evolved.
World War One and Interwar Totalitarianism intertwined the most with World War Two because of the effect they had on the countries, causing the war to begin.