Understanding early 20th-century electoral reforms requires looking beyond seat-maximizing logic. This study examines how German legislators (1890-1920) strategically formed district-level alliances to counter socialist threats, even under non-proportional systems.

Data & Methods: Using detailed records of candidatures and roll call votes from 1890–1920 Germany alongside simulations for 29 countries (1900-31), we analyze legislative behavior.

The Key Question: How did MPs' interests drive electoral system changes?

### Findings:

* Legislators sought district-level influence, not necessarily overall seat gains.

* Strategic alliances were a crucial tool to manage perceived threats from socialist parties.

* PR reforms in Germany didn't emerge solely from MPs wanting more seats but as a response to intra-party dynamics and the search for legislative control through candidate selection.

### Why This Matters:

This research challenges dominant narratives by highlighting that MPs' incentives often differed from party leaders'. Their pursuit of district-level power required unique institutional arrangements, demonstrating that electoral system choices were shaped not only by political theories but also by internal political calculations.