>>531943609
There was either
>Two Wars. After the first small war it was estabilished a short period of peace that the Orokin took control of Tau and the Tenno were sent there for cultural exchange and to learn, much like it was intended for the Zariman as colonizers but Separatists would threaten it under the belief we just surrendered the lands of Tau to the Orokin who were there to take over. After whatever else, peace is broken and the actual Old War happens
or
>the Old War as we know it encompasses a temporary period of peace midway.
The racist cephalon notes the Sentients attacked first, which is in line with the lore as we know it. And the exchange explains the existence of Caliban Prime as well.
Either way, there was an attack by the Sentients, a period of peace which the Tenno would live in Tau, in this period there was still NO reservoir and the Tenno donned their Warframes.
This also explains why Hunhow would believe Warframes were just puppets. They even have a Caliban Prime there shackled.