The objective is to show that the known features of global average sea-level over the last 120,000 years can be accounted for by eleven periodic functions associated with planetary orbits – the hypothesis. The method shows that proxy data for relative global average sea-level during the last glacial cycle, with errors measured in meters, and a modern sea-level reconstruction based on tide gauges, with errors measured in millimeters, are accurately fit using these periods and a single constant. The eleven periods, sine and cosine for each, and constant correspond to twenty-three functions. Reasons for including each period are provided. The fit predicts a maximum in global average sea-level on date 9,726 with elevation 12 meters above the 1930 level. Reasonable variations of the input data also predict a maximum in global average sea-level between years 9,726 and 12,605.