Archaeological excavations at “Doorn Noord” (Ninove, East Flanders, Belgium) revealed a complex of traces of human activity and occupation, spanning several millennia. The youngest finds consist of a vast number of surficial hearths and hearth pits, that are interpreted as the remnants of military camps. Based on direct and indirect historical information, as well as a few diagnostic finds, these traces were originally assigned to possible phases of encampment in 1692 CE, 1693 CE, 1745 CE and/or 1831–1838 CE. Although widely used in archaeological research, it is well-known that radiocarbon (14C) dating lacks precision for post-1650 CE features and therefore does not allow allocating a particular trace to a distinct phase of military presence. In this study, we report on the potential of optically stimulated luminescence (OSL) signals of quartz for directly dating the heated sedimentary remains of the hearths. We consider it a test of both accuracy and precision given the availability of independent age information (historical sources and archaeomagnetic dating). Six samples from three features yielded indistinguishable optical ages, with an average age of 1748 ± 39 CE (95% probability). This OSL date coincides with historical and archaeological evidence for the presence of a large army in this area in 1745 CE. As sources of systematic uncertainty are (largely) shared, it is possible to distinguish between comparable features with a relative time-resolution of ∼2%. For hearths from the last few centuries (post-1650 CE), this implies that numerical and relative chronologies can be established on decadal and multi-annual timescales with 95% confidence. •Quartz-based OSL dating of hearth remains from (early) Modern times.•Average OSL age (1748 ± 39 CE; 95% probability) matches independent age (1745 CE).•A relative time-resolution of 10 years with 95% probability can be achieved.•The level of accuracy and precision are unprecedented.•Wide relevance and potential of OSL-chronometry of sediments heated during (early) Modern times.