The first wholly realistic determination of the length of the Post-glacial time in S. Sweden was made by N. O. Holst and published in 1909. His calculations were based on a combination of archaeologic dating of peat horizons in a bog in S. Scania and rough estimates of rates of deposition for the same bog profile. According to his calculations the length of the Post-glacial time (sensuHolst) was 6,900 years. In 1910 G. De Geer presented the preliminary results of an investigation with the purpose of establishing an absolute chronology for the Late-Quaternary time based on varve measurements and varve connections. He also introduced a new subdivision of the Late-Quaternary time based on certain events during the deglaciation. His conclusion was that the Gotiglacial time began about 12,000 years ago. The first more detailed absolute chronology for S. Sweden was presented in 1935 by Tage Nilsson. The basic part of the chronology was a complete pollen zone system for Scania. The connection with the calendar of the Christian era was achieved for the last 4,500 years by pollen analysis of archaeologically dated finds and for older parts on varve-dated events and on interpolations based on statistical treatment of rates of deposition for the whole investigated area. The stages of the Baltic development were also connected to the chronology. It was later improved by the use of radiocarbon dating and the results of a revision of the Swedish varve chronology, but surprisingly small corrections had to be made, indicating the high standard of the basic work. Investigations in Blekinge by B. E. Berglund showed that the Scanian pollen zone system was valid also there with only small corrections in the absolute chronology. Berglund has also added more details to the South Swedish absolute chronology by investigations concerning the age of the different transgressions in Blekinge. He has further confirmed T. Nilsson's assumptions about the possibility of finding Bölling sediments in Scania.