Skyrim Lore: Is the Dragonborn lore of emperor lineage already existing in Oblivion or supplemented later for Skyrim?

I started playing Skyrim and not Oblivion in the ES series.

Are there other interesting facts or lores deliberately supplemented to the universe from Morrowind > Oblivion and also other Oblivion > Skyrim?

Edit: Are there dragons (as enemy?) in Oblivion or other ES games?

Solution 1:

To the question in the title: Eeeh kinda?

There's no such thing as Shouts in the earlier games so the emperors don't go around Fus-Do-Rahing enemies off a cliff (too bad, might have saved the emperor in oblivion from getting killed).

However, the Amulet of Kings can, in lore, only be worn by someone with the blood of a dragonborn, so dragonborns existed and were mentioned. Though I recall in Oblivion the reference was more to that lineage being blessed by Akatosh.

To the question in the the... question, they are all the same universe, set some time apart. Books have survived from the very first game and the concept of time (the dragon) breaking is a thing in all of them (this also explains how all the games are canon despite having such freedom of choice).

Solution 2:

To add to the previous answer:

Shouts do not exist as game-play mechanic in earlier games, but they very much exist in the lore from Morrowind onward. Children of the Sky tells of the Nords' ability to use their voices in battle, and of their mightiest warriors called "tongues". However, Children of the Sky does make no connection between the Dragonborn and shouting; it more so seems like shouting was a quite common ability among Nord warriors.