The first scientific journals were founded in 17th century Europe, at a time of Louis XIV, Baroque art, extensive warfare, and the Scientific Revolution. In January 1665, the French publication Journal des sçavans (journal of savants) was the first on the scene with a mix of science, history, and law, morphing later into a literary journal which no longer publishes significant scientific results. 3 months later the English Philosophical Transactions of the Royal Society started publishing, philosophical referring to natural philosophy which would now be called science. The journal is still active  and can be considered the world's oldest exclusively scientific journal.
Alphabetical listing of journals
Here is a collection of journals split into separate pages based on the first letter of the journal name. The list includes the full journal title and the standard abbreviation of the journal title.