Flags often imitate or are influenced by other nations, creating “flag families.” For example, the Netherlands’ red, white and blue flag from the 1500s set a precedent.

The U.S., France, Chile and more all have this commonality: red, white and blue flags. Here's why, as explained by Ted Kaye of the North American Vexillological Association.

The LAPD's decision to ban Thin Blue Line flags from its stations' lobbies has pulled the department into the national spotlight and shows how divisive the banner can be.

Flags often imitate or are influenced by other nations, creating “flag families.” For example, the Netherlands’ red, white and blue flag from the 1500s set a precedent.

According to Kaye, red, white and blue dominate flags due to dye technology, imitation and symbolic meanings. Historically, these colors were practical because white could be created by bleaching ...