This picture shows H P Hanssen delivering a speech at Denmark’s reunification celebrations on 11 July 1920, at the entrenchments at Dybbøl (built during the Schleswig Wars). This place later became the symbol of the Danish defeat in 1864 by Prussia and the surrender of the Duchies Schleswig and Holstein.
Denmark had been forced to surrender the Duchies of Schleswig and Holstein after the Second Schleswig War (1864). Large numbers of predominantly Danish-minded people living in northern Schleswig (now Sønderjylland) were from that point forced to live under German rule.
After World War One the Treaty of Versailles (Art 109) stated that plebiscites, or referendums, should be held in Schleswig to determine the future of the region. The referendums were an opportunity for every member of an electorate to cast their vote on a single issue, usually of national or international relevance. While the southern part of Schleswig, Zone 2, voted in favour of Germany at the plebiscite on 10 February 1920, the northern part, Zone 1 voted in favour of Denmark. As a consequence Schleswig was divided in two and the northern part formally became Danish territory on 15 June that year.
When the two zones were reunited in 1920, people all over Denmark celebrated. Hanssen was one of the leading figures of the Danish movement in Schleswig.