Since the global financial crisis, major central banks gradually switched to unconventional monetary policies (UMPs) as part of their efforts to directly influence the long-term interest rates. This study analyzes the impact of conventional/unconventional monetary policies on sovereign bond return spillovers across countries and maturities since February 2007. Following the Taper Tantrum of mid-2013 and the ECB's policy convergence to other major central banks in 2015, the long-term return connectedness across countries increased, overtaking the short-term connectedness and lowering the dispersion of connectedness measures across maturities. Over the same period, net connectedness from short- to long-term maturities weakens, while net connectedness from medium- to long-term maturities stays strong. Finally, panel regression results show that UMPs in the form of higher central bank asset ratios led to higher pairwise long-term return connectedness even when the control variables such as trade and portfolio investment flows and the distance between pairs of countries are included in regression analysis.