Holocene lacustrine records from around Iceland provide the most complete record of terrestrial Holocene climate change. We summarize the main conclusions derived from two lakes in Iceland; Haukadalsvatn, a non-glacial lake in northwest Iceland; and Hvitarvatn, a glacial lake below Langjökull, a large ice cap in central Iceland. Physical and chemical proxies (magnetic susceptibility, TOC, biogenic silica, density, ice rafted debris) in the lake sediments were analyzed at decadal to sub-decadal resolution; diatoms were analyzed in Hvitarvatn and centennial resolution. Both lake records begin close to 10 ka BP, and show the warming from deglacial cold times into the early Holocene thermal maximum, reaching a Holocene thermal maximum between 8 and 6 ka ago. By 6 ka, Langjökull had started to re-form, and primary productivity began to decline in the non-glacial lake. Conditions generally become more severe between 3 and 2 ka ago. The interval from 2000 to 800 BP is characterized by a covariant pattern of biogenic silica and TOC, indicating relatively stable climate. A moderate Medieval Warm Period shows up in our records between 1200 and 800 BP. About 800 BP, a sharp increase in TOC coincides with a decline in biogenic silica. This decoupled pattern between the two proxies intensifies after 600 BP, ending about 100 BP. The d13C of total organic carbon in Haukadalsvatn sediments during this interval (800 to 100 BP) indicates that carbon in the lake sediments was dominantly from terrestrial sources, most likely brought into the lake by soil erosion during storm events. The timing of most intense soil erosion coincides with historically documented sea-ice intensity off the coast of Iceland during this time. The ice rafted debris (IRD) record from Hvitarvatn demonstrates that outlet glaciers from Langjokull entered the lake about 1600 AD. IRD reached a maximum flux between 1625 and 1875 AD, the peak of the Little Ice Age in this area. Glacier simulations constrained by our proxies from Hvitarvatn suggest Langjökull attained its maximum LIA volume in the 1800s; the magnitude of glacier advance suggests summer temperature depression 1 to 2 °C lower than present. Langjökull disappeared during the HTM, requiring a temperature at least 3 °C warmer than present.