What Would be the effects of Tau Empire appearing in the Mass Effect Universe?

[ThePoarter]

Let's say the Tau Empire makes first contact with Citadel Council in the year 2157, the same as humanity. No other Warhammer fraction exists in this case. Assume that everything else about the empire is the same.
What would be the inevitable effects of their appearance and how would this change everything?

Do also keep in mind that this is the Tay Empire only and we are assuming that they never interacted with the rest of the wider galaxy.

 

[Sabertooth]

I'd say they walk all over any ME faction. The Tau, naive and lucky as they are, are still someone that can match the Imperium of Man and other factions blow for blow in a highly dangerous universe.

ME is a paradise when compared to 40k.

 

[Spartakrod]

The Tau rapidly conquer the entire galaxy and obliterate the reapers.

While small by 40k standards, their empire as of the fifth sphere expansion in the second century of the forty second millenium is absolutely massive by Mass Effect standards and probably has more soldiers than any mass effect civilization has people. Their military technology is also incomparably superior to the point of their warships being essentially invincible. The combined fleets of C-space and the Terminus Systems are probably annihilated in short order by the Tau and their planets placed under military occupation about as quickly as a Tau conquest fleet can arrive over them.

When the Reapers come they get massive sections of their fleet pulverised by single cruisers wading through it like a dreadnought waltzing through wood and sail era ships, in a proper fleet engagement the Reapers are going to suffer horrific irreplaceable losses to even the most modest of gains.

There is really nothing but internal political difficulties (which can be smoothed over by the Tau adopting Mass Effect's faster FTL comm systems) stopping the Tau from ruling the entire galaxy.