In fact, a few posts below, we learned that one of the earliest Conn Sousaphones, built in 1899 for the A. O. U. W. Military Band in Cedar Falls, Iowa, was used in in the Grand Army parade at Philadelphia on September 5th of that year. This may very well be the earliest reference to someone marching with a Sousaphone.
While I have not been able to find a photo of that horn in the parade, here is what the festivities looked like that day in Philly:
|Photo courtesy of the Library Company of Philadelphia|
|Photo courtesy of the Sousas Archives|
|Photo courtesy of the Sousa Archives|
When it comes to marching at a football game, it appears that the Notre Dame Band may have been the first to do so, although the University of Illinois Band, to which Sousa himself had ties, is also claimed to be the first - as well as the first college band to use Sousaphones.
The Marching Illini Band is also said to be the first "to spell words and perform intricate maneuvers while playing," doing do in 1910. But three years earlier, the Purdue Band began forming the letter "P" on the field, as shown - something they continue to do today.
Here's a closer look at the bass section, consisting of three Sousaphones (all "raincatchers," as this was 1907) and five Helicons:
But when it comes to Sousaphones in college marching bands, there is no tradition more well-known than dotting the "i" in the script Ohio. However, the truth is, it was the University of Michigan marching band who first performed the script Ohio in 1932 (gasp!), while the Ohio State Band didn't adopt the formation until 1936. And - get this - it wasn't a Sousaphone at first that dotted the "i" at Ohio State, but rather a trumpet player (look closely - that's clearly not a Sousaphone):