Its ANZAC day today and it's gotten me thinking about the parts of the war that weren't a part of Europe. And follow up questions, what was happening in Africa and Asia?

One of, if not the primary reason that the Conquistadors were so successful in their campaign against the Mayans, etc, was due to the diseases they brought with them from Europe. The indigenous population had no resistance to the diseases they brought, which is understandable. But why were the Conquistadors not just as easily felled by the local diseases that they had not been exposed to in Europe? Why was the harm so one sided?

I've heard many stories about Romans and their excellent "castra"s (forts/camps). With some of the pictures I've seen on the internet I'm wondering how Roman troops were able to construct such organized forts so quickly. Especially ones with stones and permanent building materials!

I've been able to find plenty of information on the design of the camps, but next to nothing on the actual construction of them, so I thought this would be the place to ask!

It seems the Senate and Patrician level families had more to lose if a tyrant came to power while the majority of people might not be effected or possibly could even benefit. Especially when it came to people like Julius Caesar who, at least on the surface, seemed much more populist than many in the Senate.

Magyars, Finns, Pechenegs, Mongols and Turks all have their origins in the Central Asian steppes. What led these societies to clash with Europeans and defeat them so effectively?

I'm asking this in /r/AskHistorians because I'm assuming that the use of forks and spoons was introduced, or influenced by, the British when they colonized the area. I recently travelled to Malaysia, and usually got a fork and spoon with my food. If this question is more appropriate for a different subreddit please let me know; I tried looking for the answer online, but have unearthed very little.

For example, did puppet states of the USSR that weren't official members of the soviet union know their country was essentially controlled by Russia? What about other puppet states through history?

I understand this question is very specific, but it's confusing me. The standard layout for US-engineered coups is, resources are nationalized, the US and domestic corporations engineer a coup, and resources are re-privatized. Except in Chile, that re-privatization never occurred. So how did Pinochet come to be seen as a bastion of hope for capitalists, if copper remains nationalized to this day in Chile? Is copper a unique case?

Was the Chilean coup less about nationalization and more about containing the Soviet sphere of influence?

Wouldn't it make more sense to call it the East Indies?

The US Secret Service seems to be the only federal agency that incorporates "United States" in their acronym. Presumably, they do this to avoid being called the "SS."

Was the Secret Service ever known as the "SS?" When did the custom of calling them the "USSS" begin?

Edit: There are other federal agencies that incorporate "US" in their acronym. It seems most of the other "US" agencies were founded before the 20th Century. Was this a 19th Century thing? Maybe to emphasize these are federal, not state, agencies?

Edit 2: I've made a few false assumptions. Demonstrating this is a helpful way to answer my question. Thank you.

I'm really interested in why burning a flag in protest gets such a strong negative reaction out of people, but I think understanding this would help.

Humans were hunger-gatherers for the longest time - what happened to make them settle down and create civilizations like Babylon or Egypt? Did a specific thing force them to do so, or was it a gradual thing, where people started to discover agriculture and so settled down?

I mean like, the first serious scientific source confirming them as mammals. I remember reading somewhere that Aristotle knew they couldn't be fish and concluded they were mammals. Perhaps I'm not googling correctly but I can't find any sources to answer my question.

I mean, there have probably been smart people since the Ancient times that found a beached dolphin or whale and realized that it was breathing and had no gills, but when did some actual taxonomer say "wait a minute"?

Just had this thought.

Especially because the new religions seem very distinct in structure, more "absolute" in a way. Was something social going on for Roman society to start favoring a different kind of religion than its old faith, eventually settling on christianity?