Historically, many comparisons have been made between George Orwell's novel Animal Farm and the Soviet Union. Underneath, many more comparisons have been made between specific characters in the novel (most prominently Napoleon) and Russian leaders (most prominently Stalin).
In order to create a thesis for a comparison between Napoleon and Stalin, while also grabbing the attention of the reader, one needs to find something which can appeal to readers who have limited or no knowledge of either the novel of the Russian leader.
In comparing both Napoleon and Stalin, historians and literature critics have found that the pair shared very specific characteristics. Both were not well known for their speaking ability (actually, both were not well educated speakers). Both were brutal, corrupt, and selfish. Lastly, both only cared about power and used those around them to gain it.
Essentially, one could create a thesis which describes the negative characteristics of both through questioning the reader's contempt for following a person like Stalin and Napoleon.
Here is a suggestion for an attention getting thesis (introduction):
Would you be swayed to follow a person who spoke intelligently, only desired power, and did not care who they used to gain control? For some, this question would provoke a resounding "no." Then why did people follow Stalin like lambs to the slaughter?--Perhaps for the same reason that the animals of Orwell's Animal Farm followed Napoleon. The comparisons between Stalin and Napoleon have hit too close to home for many (given its pseudo-banning in the 1940s). Is there a true tie between the character of Napoleon and Stalin? Some, like myself, have no doubts.