World War II had ended just three years before and the Federal Republic of Germany had not yet come into existence when the first edition of STERN magazine, with 130,735 copies, hit the stands in 1948. Another 17 years passed before Gruner + Jahr was actually founded: In 1965, the publishers John Jahr (CONSTANZE, BRIGITTE, SCHÖNER WOHNEN, CAPITAL) and
Dr. Gerd Bucerius (STERN, Die Zeit etc.) consolidated their business operations with those of the printer Richard Gruner. A powerful printing and publishing house emerged.

The end of the sixties marked the beginning of a new chapter in the publishing house's development: Richard Gruner sold his shares in the company; Jahr and Bucerius each held 37.5 % and the Bertelsmann publisher, Reinhard Mohn, purchased a 25 % stake in the business. From 1969 to 1975, the Bertelsmann media group acquired 74.9 % in total of G+J shares in several tranches. Only one founder is still a shareholder today - the Hamburg publishing family Jahr currently has a 25.1 % blocking stake.

Gruner + Jahr strengthened its position by acquiring holdings and conducting takeovers in Germany and, from 1978 onwards, abroad. The company initially purchased publishing houses in Spain and the USA. In 1979, a printing house in the USA was the next target, namely the Brown Printing Company. As a result of the numerous start-ups and acquisitions down the years, G+J grew to become the largest periodical publisher in Europe. Today, Gruner+Jahr is the biggest publisher in Germany, the second biggest in France and has a range of international magazine brands such as CAPITAL, GEO, GALA, FOCUS/PM and PARENTS/ELTERN.

In the mid-eighties, G+J entered the newspaper sector. With German dailies and stakes in several Eastern European newspapers, an independent business unit was established. In the spring of 2000, Gruner + Jahr brought the FINANCIAL TIMES DEUTSCHLAND onto the market in a joint venture with the London media concern Pearson. This is the first new national newspaper in Germany to appear for several decades.