Read these Threads as well. The English and American Schools are not in any of the resources previously mentioned to any degree.
Prescotts and other 1800s Yankee Basses The English School of Double Basses
More about this and other schools on my own forum if you have the time.
The German/Viennese (Austro-Hungry) school developed simultaneously along with the Italian School but went into a slightly different direction than the Italians with the exception of the Viol d'Gambas which were never uniform even within the same country and period. The French flourished mainly in the 19th century but with not much contribution to the advancement of Bass making.
The English made the greatest Basses collectively from the late 18th thru the mid 19th centuries copying mainly the Italian models with the focus on the Brescian model (Maggini) but modified earlier mainly by Panormo who was influenced by Strad and a great imitator of his style in his Violins. Panormo made chiefly round/carved Backs on his personal Basses but when working in the Betts shop he made what was ordered of him. Most all other English makers used a FlatBack on their Basses with only a few exceptions. I own 3 English Basses now (of 4 I have purchased) and only one has a round back and a rare Bass all around.
The early American School copied mainly the German models but some Scrolls are more similar to English Viols. Kind of a mix in design. My link included above or English and American Basses.
I helped my Son do the same project 2x in School. For his senior project, we did a duet with a 200 year old Italian bass (me playing) and a modern Smith Electric Bass (him playing) with history told from Gasparo d'Salo to Fender. He did well!
Schools.. 
