Carl Friedrich von Siemens, Werner von Siemens’ youngest son, took over as “Head of the House” following the deaths of his brothers Arnold and Wilhelm in 1918 and 1919, respectively. He continued to head the company until his death in 1941.

Through World War I, Siemens had lost 40 percent of its capital. Most of its foreign assets and almost all of its patent rights had been expropriated. The most urgent tasks during the immediate postwar years were the reorganization of the company’s expanding manufacturing operations and the revitalization of its foreign business.

One of Carl Friedrich von Siemens’ policies was to service the whole of the field of electrical engineering but to assign individual areas of business to specialized subsidiaries and related companies. Siemens, AEG and Auer-Gesellschaft accordingly merged their incandescent lamp businesses in a joint venture, Osram GmbH; Siemens-Elektrowärme GmbH took over the manufacture of household appliances and heaters and Siemens & Halske AG’s Electrical Railways Division became Siemens Bauunion. Medical engineering was now the responsibility of Siemens-Reiniger-Werke AG. The formation of Siemens Planiawerke AG led to the creation of Europe’s largest factory for the manufacture of carbon electrodes.

Each of the spun-off and newly formed companies maintained recognizable ties with their corporate parent. One important factor here was a consistent corporate identity that helped underscore their common origins. In the 1930s, Hans Domizlaff established a unified approach to advertising and consistent company-wide branding.

Partly under the influence of Carl Köttgen, manufacturing was reorganized around assembly lines. This tapped considerable potential for rationalization and ensured that production remained cost-efficient.

In the 1920s, Siemens-Schuckertwerke GmbH received the largest foreign contract awarded to any German company since the turn of the century when it was hired to build a power plant on the Shannon River. The power generated by the facility was used to electrify the whole of Irish Free State. In 1923, Siemens-Schuckertwerke GmbH and Japan’s Furukawa group launched a joint venture, Fusi Denki Seizo KK, to manufacture electrical products in Japan.

The official recognition of trade unions by the stat and employers paved the way for a new company welfare policy. The primary focus of policy was on the provision of retirement benefits, an issue that Werner von Siemens had originally addressed in 1872 with the formation of a pension fund. Besides reintroducing a year-end annual bonus in 1927, the company also implemented a corporate housing initiative, began offering rest and recovery programs in company-owned facilities, and provided support for employees’ leisure activities.