Globular cluster age distributions in the MW from Forbes & Bridges (2010), Dotter et al. (2010, 2011), VandenBerg et al. (2013), and Cabrera-Ziri & Conroy (2022), split up according to their likely progenitors from Forbes (2020). The shown classifications are the total population (all), GSE, the unassociated high-energy GCs (H-E), and the Helmi Streams (H99). The total number of GCs in the respective sample is indicated in the top left. The shaded region between 8 Gyr and 11 Gyr indicates the estimated time of the GSE merger (Belokurov et al. 2018; Helmi et al. 2018). See Fig. 3 for the corresponding age distributions smoothing the data points through their uncertainties.