We studied an upland forest located within the Grand Prairie region of Illinois and utilized tree-ring analysis to document tree cohort development and radial growth in relation to stand disturbance and climate. The overstory within the Humiston Woods Nature Center (Livingston County, Illinois) study area was dominated by oak (Quercus spp.), hickory (Carya spp.), and ash (Fraxinus spp.), while the subordinate crown classes were principally composed of elm (Ulmus spp.) and sugar maple (Acer saccharum). The study area contained tree cohorts originating during two recruitment periods. Overstory oaks and hickories primarily established between 1865 and 1900. A second tree cohort was associated with a timber harvest occurring in the late 1960s. In contrast to the 1865–1900 recruitment period, trees within the 1965–1980 cohort were primarily ash, elm, sugar maple, and black cherry (Prunus serotina). RWI values were most strongly correlated with Palmer Drought Severity Index, precipitation, and temperature in June of the current growth year. RWI and radial increment data for overstory oaks highlighted a sustained growth increase following a late 1960s timber harvest that remained high relative to predisturbance growth rates even in pronounced drought years. Data provide needed insight into oak woodland recruitment patterns relating to disturbance regimes that are difficult to recreate at the landscape level but often serve as ecological restoration objectives. Our findings help extend the foundational knowledge regarding forest composition, stand level dynamics, and radial growth relationships present among upland forests and changing disturbance patterns in the Grand Prairie region of Illinois.