Hollandsche Bank-Unie (HBU) was a second-tier domestic bank in the Netherlands that Deutsche Bank absorbed in 2010. It had a notable international history.
On 28 March 1914, the Rotterdamsche Bank, together with the Nederlandsche Handel-Maatschappij (NHM) and several smaller firms, established the Hollandsche Bank voor Zuid-Amerika (Holland Bank for South-America). The bank opened in Buenos Aires under the name Banco Holandés de la América del Sud (Banco Holandés). In 1916 the bank opened a second branch in Rio de Janeiro, and in 1919 a branch in São Paulo. By 1922, the Hollandsche Bank voor Zuid-Amerika was running branches in Genoa, Hamburg, Buenos Aires, Rio de Janeiro, Santos, Santiago, São Paulo and Valparaíso.
In 1918 the Rotterdamsche Bank and the NHM, together with smaller shareholders such as the Royal West India Mail/Royal Netherlands Steamship Company and the subsidiary of Shell that ran Curaçao's refinery, as well as Bank of Suriname decided to create a similar bank for the West-Indies. The Hollandsche Bank voor West-Indië was established with head office in Amsterdam to operate branches in Willemstad, Curaçao. In 1920 this bank was the first European bank to open a branch in Caracas.
In 1919, a year after the founding of Hollandsche Bank voor West-Indië, the Rotterdamsche Bank joined with the Hollandsche Bank voor Zuid-Amerika to establish the Hollandsche Bank voor de Middellandsche Zee (Holland bank for the Mediterranean). It opened branches in Genoa, Barcelona, Marseilles, Constantinople, and later Tel Aviv.