Before Alaska was the largest state in the Union, Texas was biggest and boldest. Arguably Texas may still be the boldest but she ain't the biggest anymore. Also note the basic design for the Largest Flag of a Geographic Group is based upon the state flag of Texas.
Even before Texas the title of the biggest state was held by Missouri. Before Missouri, Virginia was the supersized state. Before Virginia, Georgia was largest. Before Georgia, Pennsylvania was the big boy. And it all started with Delaware.
Delaware had a short five day sprint as the biggest state in the USA from December 7, 1787 until December 12, 1787.
Pennsylvania had a bit longer run for about three weeks from December 12, 1787 until January 2, 1788.
Georgia was the biggest state in the USA for half a year from January 2, 1788 until June 25, 1788.
For 33 years from June 25, 1788 unto August 10, 1821 Virginia was the biggest kid on the block. During Virginia's reign as the big chief of America, the first official Commander and Chief of the United States was coincidentally from Virginia - George Washington. Furthermore when Virginia was the proverbial biggest big sister of America, she was also in charge most of the time under Virginian born presidents: Jefferson, Madison, and Monroe. Also note it was when Virginia was whole, before the US Civil War.
For a long 24 years Missouri was the biggest kid on the block from August 10, 1821 until December 29, 1845. Unfortunately most people don't remember Missouri's role as the big man of America. Amazingly and coincidentally the state flag Missouri also has 24 stars, reflective of the 24 years when Missouri was Big Mo.
Since Alaska is now the Big One of America, she gets fly this without any mark - you can see it here. But for Canada the unmarked version flag belongs to Nunavut, since April Fool's Day 1999, but its just a territory. Ironically for Mexico this flag belongs to one of the most popular small dogs - the tiny Chihuahua , but in this case Chihuahua is the Alaska of Mexico by area. For Russia this flag belongs to Sakha, sine its the biggest sub-federal subject of Russia.