Well, at first glance we tend to think every civilization emerged from glorious conquest. That is true for all civilizations who followed after the very first. But who were the first Civilizations?
Personally, i dont subscribe to the belief the human race migrated out of Africa slowly inhabiting the rest of the world. Why? Because there are continually new archeological findings all over the world that have turned the Africa theory upside down. From a preserved aboriginal mummy found in Australia to countless new pre-historic artifacts in Germany and Spain. These findings along with the advancement of DNA sequencing have thrown into question the legitimacy of a "one race" evolving out of Africa.
I believe there were three main original human races. The European Caucasian, Asiatic and African races. Whats more interesting are the extinct humanoid races that have been found in Papua New Guinea. As technology advances we're able to look deeper and deeper into our past. Currently our History is limited to Civilizations who developed a mode of written text to record events and communicate. History goes back much much farther then that!
Long comment short. These original peoples would be the only Civilizations to have emerged without bloodshed. Once the population continued to grow, migration took place, filling up all corners of the globe. Boarders and Kingdoms were founded and thus the great civilizations began battling over power and land.
The people who migrated to new lands and later built Civilizations would be the answer to your question. There is a difference between 'emerged' and 'defended'.
A few civilizations that i would consider who rose without bloodshed are...
Celts (Europe)
Early Germanic Vikings (Europe)
Xia Dynasty (China)
Songhai Empire (Africa)
I wont not consider the Aztec Empire a bloodless civilization because they arose out of the conquest of neighboring tribes. Like i said, there is a difference between 'emerging' and 'defending' I believe all the civilizations have had to 'defend' themselves at one point in time, but thats different then emerging without bloodshed.