A few off the top of my head: - Given that Augustus allowed his BFF provincial governors to strike coins, and that so many provincial coins were made for Gaius and Lucius, why were none made for Nero Claudius Drusus while he was Caesar? - With the sole exceptions of Vindex and Clodius Macer, how come no usurpers struck coins until the 193-197 AD civil wars? Avidius Cassius, in particular, seems like he should have issued coins? - Even though Lucius Verus clearly took a back seat to Marcus Aurelius, I was surprised to learn that there is not a single extant coin of Verus struck while Pius was still alive, not even provincial as far as I can tell. - Given their popularity, it seems a bit strange that Gordian I and II were never honored on posthumous coins by Balbinus, Pupienus, or Gordian III? - History tells us that Philip I had Gordian III deified, but no coins exist compared to Philip's otherwise extensive series of commemoratives? - Decius' "Best Emperors" set likewise has its own mysteries... -- If Commodus made the cut, why no Claudius? -- Severus Alexander and Commodus made the cut, but none of the three Gordians, all three of whom Decius was a dedicated supporter of? - Considering the trouble that Gallus went to in order to adopt Hostilian and ensure a smooth transfer of power, Decius wasn't honored with a posthumous coin? - Gallienus was supposedly made Caesar briefly before being raised to the purple in 253, yet no coins exist? - There are Saloninus coins muled with the posthumous Valerian II reverses, but I have yet to see any photographic evidence of a posthumous Saloninus minted after 260. - After all the "Restitutor Orbis" hoopla, Tacitus didn't think Aurelian deserved a consecration coinage? - Maximian was Caesar under Diocletian for almost a year (summer 285 to spring 286) yet no coins exist? (This has me wonder if the antoninianii of "Galerius" without GAL VAL could be a Maximian caesar?) - Constantine allowed himself to be declared Augustus after his father's death in 306, and he at least controlled the London mint at this time, yet no coins? Perhaps that was too big of a risk? - Constantius, Maximian, and even Galerius were all honored on consecration coins, but not Diocletian, who was arguably the only member of the Tetrarchy that everyone liked? - I know that it became the standard practice to elevate kids and even toddlers to the purple, but it struck me as odd that Julian is the last person to strike coins as Caesar. Conversely, I did learn some surprising facts about coins I *didn't* think should exist, but do: - Coins of Diadumenian as Augustus do exist, even four from Rome: https://www.acsearch.info/search.html?id=2176841 - Coins of Herennius Etruscus as Augustus exist, but are much more rare than I initially thought: https://www.cngcoins.com/Coin.aspx?CoinID=247009 - Coins of Volusian as Caesar exist, and are much more rare than those of Hostilian as Augustus https://www.cngcoins.com/Coin.aspx?CoinID=162951 - There is supposedly a single coin of Quintus Julius Gallienus Caesar, a younger brother of Valerian II and Saloninus, who maybe died in infancy: http://numismatics.org/ocre/id/ric.5.qjg.1 - There is an entry for DIVO QVINTILLO - but who would have consecrated him? http://numismatics.org/ocre/id/ric.5.qu.15 - Tetricus consecrated Victorinus? https://www.cngcoins.com/Coin.aspx?CoinID=340542 - Tetricus II as Augustus is known from many barbarous coins, and supposedly from at least one official. I managed to snag a barb: - Maxentius, who never considered himself anything less than full Augustus, has a small issue of coins of MAXENTIVS NOB CAES from Carthage: Please share any insights on my aimless musings above, or other historical curiosities!