Bismarck's rhymes with:
benchmark's, benchmarks, birthmarks, caremark's, cellmark's, denmark's, deutschemark's, deutschemarks, earmarks, hallmark's, hallmarks, hartmarx, landmark's, landmarks, pathmark's, raymark's, southmark's, trademarks, watermarks, westmark's
Bismarck's sounds like:
beginner's, beginners, besner's, bismarck, bismark, bookmark, bookmarks, buccaneers