A form of flags had been designed for naval battles all over the Civil War; these integrated distinguishing marks for ships

https://paxtonlita906.publishlane.com/posts/flags-that-changed-history-the-stories-behind-famous-civil-war-banners-2

A form of flags had been designed for naval battles at some stage in the Civil War; these incorporated distinguishing marks for ships engaged in strive against on rivers and seas alike.