How many letters does the top answer for “war that began in 1648” have?

The most common answer is fronde (6 letters).

Crossword clue: war that began in 1648

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

fronde 6 letters wd-fact-v3

A political party in France, during the minority of Louis XIV., who opposed the government, and made war upon the court

war that began in 1051 100% similar → zenkunenwar

war that began in 1095 100% similar → crusades

war that began in 1096 100% similar → firstcrusade, peoplescrusade

war that began in 1135 100% similar → theanarchy

war that began in 1147 100% similar → secondcrusade

war that began in 1156 100% similar → hogenrebellion

war that began in 1160 100% similar → heijirebellion

war that began in 1180 100% similar → genpeiwar