On an aside, while not something that is mentioned or discussed during the interview, it appears then that each civilization in RoN has identifiable leaders as is characteristic of its turn-based counterparts.
I PLEDGE MY ALLEGIANCE
Alliances are a consideration of a more elaborate sort. If such terms are agreed upon, participating nations will be able share in each others' line of sight, move in and out of each other's territory at will and even do the otherwise unthinkable and erect buildings within each others' boundaries. In all cases also: things built up in co-operation of this venture count towards mutual benefit and victory. This is new ground for the genre unto itself. In practice, this theory allows for joint victories and defeats on the foundation of Wonder manufacture, military objectives, and even politically: as soon as your combined territories equal or exceed 70% of available in-game terrain, you are recognized as evenly dominant forces.
Declaration of joint aggression – in other words, a common military effort – is also a possibility to explore (or even exploit, as the case may be). Undoubtedly, this is a most serious undertaking. Often you will encounter a situation where an agreement for alliance must also be compounded with concessions of varying types and magnitudes. You needn't worry about falling victim to a renege: all exchanges, allegiance-based or otherwise, are simultaneously conducted to avoid what Reynolds calls "cheap tricks", for example, "to get someone to declare war on somebody else without actually following through [to do the] thing [they] promised".
As we have now discussed, a series of proposals and counter-proposals are the basis for a majority of these discussions. This may not seem like a lot or terribly innovative at first, but remember we are talking about a real-time strategy (RTS) environment here – we are venturing into largely uncharted waters of game design.
"We really had to do a lot of work to be able to get a diplomacy system that a) allowed you to have a little bit more flexibility than just war [and] peace", Reynolds explains. "So, it kind of went beyond what had normally been done in [RTS] games and be something that you can make sense of in a real-time context [via] time frames. So, if I am here talking to Emperor Napoleon I'm not giving orders to my troops".
Rise Up: Reynolds On RoN 