Bertha Krupp von Bohlen und Halbach (29 March 1886 – 21 September 1957) was a member of the Krupp family, Germany's leading industrial dynasty of the 19th and 20th centuries. As the elder child and heir of Friedrich Alfred Krupp she was the sole proprietor of the Krupp industrial empire from 1902 to 1943, although her husband, Gustav Krupp von Bohlen und Halbach, ran the company in her name. In 1943 ownership of the company was transferred to her son Alfried.
Bertha Krupp was born in Essen, home of the Krupp family and their company since the 16th century. Her mother was Baroness Margrethe von Enden. At the time of Bertha's birth the company was owned and managed by her grandfather Alfred. Upon his death the following year, her father Friedrich inherited ownership and control. Her sister Barbara was born in 1887 (d. 1972), but the absence of a male heir put the future of the company in doubt.
Friedrich Krupp died in 1902, leaving Bertha as the heiress to the Krupp interests. However, it was considered unthinkable for a woman to exercise control over the vast Krupp coal, steel and armaments empire. In 1907, therefore, Kaiser Wilhelm II personally led a search for a suitable husband for Bertha. The Kaiser found him in Gustav von Bohlen und Halbach, a professional diplomat of good family and a familiar figure at the Kaiser's court. They were married on May 7. On that date, Gustav added the name Krupp to his surname and assumed executive control of the company. Barbara received a large cash settlement and Bertha became sole owner of the company.
Gustav and Bertha had eight children: Alfried (1907–67), Arnold (1908-1909), Claus (1910–1940), Irmgard (1912–1998), Berthold (1913–87), Harald (1916–85), Waldtraut (1920–2005) and Eckbert (1922–1945). Of these only Alfried as the eldest son took the surname Krupp von Bohlen und Halbach. The others used the surname von Bohlen und Halbach. Claus and Eckbert were killed on active service in World War II, and Harald spent ten years in captivity in the Soviet Union.
During World War I, the Krupp company manufactured large mortars that the German army used to bombard forts in Belgium and France. German troops nicknamed these Dicke Bertha ("fat Bertha") after Bertha Krupp von Bohlen und Halbach. Allied troops used the translated name, "Big Bertha," to refer to all German long-range artillery, particularly those that shelled Paris in 1918. However, "Big Bertha" entered the lexicon due to a piece of German artillery which was constructed of three artillery barrels welded together. It had a range of 75 miles and its appearance was a major surprise to Parisians in 1917 who had previously only come under attack from German aircraft, since previous artillery reached a maximum of thirty miles.