Napoleon The Third
Napoleon III
noun
Adding "third generation" to someone's name means that they are the third generation of people with that name. In this case, the person's name is ナポレオン (Napoleon), so this means Napoleon The Third, also written as Napoleon III.
なぽれおんさんせい
ナポレオンさんせい
The kanji here are pronounced exactly the same as in the standalone word 三世. That is, it's a jukugo word which uses the on'yomi for both kanji.
今日は、ナポレオン三世について学びましょう。
Today, we're going to learn about Napoleon The Third.
ナポレオン三世は1808年に生まれた。
Napoleon III was born in the year 1808.
ナポレオン・ボナパルトはナポレオン三世より有名ですよね。
Napoleon Bonaparte is more famous than Napoleon III, isn't he?