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Abstract. Strong similarities in Holocene climate reconstructions derived from multipleproxies (BSi, TOC – total organic carbon, δ13C, C∕N, MS – magnetic susceptibility, δ15N)preserved in sediments from both glacial and non-glacial lakes across Icelandindicate a relatively warm early to mid Holocene from 10 to 6 ka,overprinted with cold excursions presumably related to meltwater impact onNorth Atlantic circulation until 7.9 ka. Sediment in lakes from glacialcatchments indicates their catchments were ice-free during this interval.Statistical treatment of the high-resolution multi-proxy paleoclimate lakerecords shows that despite great variability in catchment characteristics,the sediment records document more or less synchronous abrupt, colddepartures as opposed to the smoothly decreasing trend in Northern Hemispheresummer insolation. Although all lake records document a decline in summertemperature through the Holocene consistent with the regular decline insummer insolation, the onset of significant summer cooling occurs ∼5 ka at high-elevation interior sites but is variably later at sitescloser to the coast, suggesting that proximity to the sea may modulate the impactfrom decreasing summer insolation. The timing of glacier inception during themid Holocene is determined by the descent of the equilibrium line altitude(ELA), which is dominated by the evolution of summer temperature as summerinsolation declined as well as changes in sea surface temperature for coastalglacial systems. The glacial response to the ELA decline is also highlydependent on the local topography. The initial ∼5 ka nucleation ofLangjökull in the highlands of Iceland defines the onset of neoglaciationin Iceland. Subsequently, a stepwise expansion of both Langjökull andnortheast Vatnajökull occurred between 4.5 and 4.0 ka, with a secondabrupt expansion ∼3 ka. Due to its coastal setting and lowertopographic threshold, the initial appearance of Drangajökull in the NWof Iceland was delayed until ∼2.3 ka. All lake records reflect abruptsummer temperature and catchment disturbance at ∼4.5 ka, statisticallyindistinguishable from the global 4.2 ka event, and a second widespreadabrupt disturbance at 3.0 ka, similar to the stepwise expansion ofLangjökull and northeast Vatnajökull. Both are intervalscharacterized by large explosive volcanism and tephra distribution in Icelandresulting in intensified local soil erosion. The most widespread increase in glacier advance, landscapeinstability, and soil erosion occurred shortly after 2 ka, likely due to acomplex combination of increased impact from volcanic tephra deposition,cooling climate, and increased sea ice off the coast of Iceland. All lakerecords indicate a strong decline in temperature ∼1.5 ka, whichculminated during the Little Ice Age (1250–1850 CE) when the glaciersreached their maximum Holocene dimensions.