Black carbon (BC, synonymous to charcoal or soot) has received increasing attention owing to its potential importance in a wide range of biogeochemical processes. Due to BC's relative resistance to degradation, experiments investigating the long-term changes in BC properties are a challenge and overall information about biogeochemical changes of BC still remains scarce. In this study, we collected BC samples from the remnant soils of historic charcoal blast furnaces. Seven furnace sites in eastern America, with mean annual temperatures ranging from 4.4ºC in Maine to 17.7ºC in Alabama having similar operation history and abandonment time, were chosen. X-ray Photoelectron Spectroscopy (XPS) was used for evaluating oxidation of BC that were isolated from soil. We also measured the Potential Cation Exchange Capacity (P-CEC) and Effective CEC (E-CEC) of total soil to determine changes in surface charge associated with oxidation. XPS showed that BC particles from higher temperature regimes had higher atomic O/C ratio than BC from lower temperature regimes. Similarly, both E-CEC and P-CEC were higher at locations with high mean annual temperature, when the CEC was normalized for organic C contents of the soils. The significant linear relationships were slightly stronger between O/C ratio and temperature (r = 0.95), than between P-CEC/C and E-CEC/C and temperature (r = 0.92 and 0.88, respectively). The strong relationship between atomic O/C ratio and mean annual temperature showed that oxidation of BC particles is significantly controlled by temperature. The slightly lower relationships for E-CEC/C and P-CEC/C were a result of different soil properties. Considering the large variation of soil types, mineralogy, pH and vegetation, the relationship between CEC and temperature was remarkable strong. These results can be used to improve the quantification of BC sinks in the global C cycles as well as inform management decisions of bio-char soil technologies.