“fight / war” in Japanese is 戦, read sen, tataka (せん, たたか). It is a Grade 4 Kyōiku kanji, taught in year 4 of Japanese elementary school, and appears in words such as 戦争 (war).
What does 戦 mean?
むかしは戦があった。
Same sound, different character — the classic trap. Compare them side by side: