Scheele was born in Stralsund, in western Pomerania, which at the time was a Swedish Dominion inside the Holy Roman Empire. Scheele's father Joachim (or Johann) Christian Scheele, was a grain dealer and brewer from a respected German family. His mother was Margaretha Eleanore Warnekros.
Friends of Scheele's parents taught him the art of reading prescriptions and the meaning of chemical and pharmaceutical signs. Then, in 1757, at age fourteen Carl was sent to Gothenburg as an apprentice pharmacist with another family friend and apothecary. (Martin Andreas Bauch). Scheele retained this position for eight years. During this time he ran experiments late into the night and read the works of Nicolas Lemery, Caspar Neumann, Johann von Löwenstern-Kunckel and Georg Ernst Stahl (the champion of the phlogiston theory). Much of Scheele's later theoretical speculations were based upon Stahl.
In 1765 Scheele worked under the progressive and well informed apothecary, C. M. Kjellström in Malmö, and became acquainted with Anders Jahan Retzius who was a lecturer at the University of Lund and later a professor of chemistry at Stockholm. Scheele arrived in Stockholm between 1767 and 1769 and worked as a pharmacist. During this period he discovered tartaric acid and with his friend, Retzius, studied the relation of quicklime to calcium carbonate. While in the capital, he also became acquainted with many luminaries, such as:
Abraham Bäck, Peter Jonas Bergius,
Bengt Bergius and
Carl Friedreich von Schultzenheim.
In the fall of 1770 Scheele became director of the laboratory of the great pharmacy of Locke, at Uppsala which is about 40 miles north of Stockholm. The laboratory supplied chemicals to Professor of Chemistry Torbern Bergman. A friendship developed between Scheele and Bergman after Scheele analyzed a reaction which Bergman and his assistant Johan Gottlieb Gahn could not resolve. The reaction was between melted saltpetre and acetic acid which produced a red vapor. Further study of this reaction later led to Scheele's discovery of oxygen (see "The theory of phlogiston" below). Based upon this friendship and respect Scheele was given free use of Bergman's laboratory. Both men were profiting from their working relationship. In 1774 Scheele was nominated by Peter Jonas Bergius to be a member of the Royal Swedish Academy of Sciences and was elected February 4, 1775. In 1775 Scheele also managed for a short time a pharmacy in Köping. Between the end of 1776 and the beginning of 1777 Scheele established his own business there.
On October 29, 1777, Scheele took his seat for the first, and only time, at a meeting of the Academy of Sciences and on November 11 passed the examination as apothecary before the Royal Medical College and did so with highest honours. After his return to Köping he devoted himself, outside of his business, to scientific researches which resulted in a long series of important papers.