ante diem iv nonas sextilias
- 338 B.C. — Death of Archidamus III (King of Sparta)
- 216 B.C. — Hannibal inflicts a massive defeat on Roman forces at Cannae (possible date)
- 86 B.C. — Sulla defeats Mithridates at Chaeronea (possible date)
- 49 B.C. — Julius Caesar defeats Afranius and Petreius (legates of Pompey) at Ilerda
- 47 B.C. — Julius Caesar defeats Pharnaces II at Zela (and would later proclaim his victory with the famous “Veni, vidi, vici” )
- 9 A.D. — death of Quintilius Varus (not sure about this one)
rogueclassicism 
Shouldn’t that be “sextilis”, not “sextilias”? Sextilis is a 3rd decl. adjective, so the acc. pl. f. (to agree with “nonas”) would be “sextilis” (with a long -i in the ending) or “sextiles”.
Yes it should … I have a recurring problem with Sextilis, Quintilis, and every now and then Aprilis … thanks for reminding me!
PS — Thanks for posting all this! I hadn’t realized that this particular day had been so eventful.