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Accurate characterization of hydrocarbon reservoirs requires a good understanding of the paleostress history of their host sedimentary basin. This study aims at reconstructing the paleoburial and paleostress history of the syn-rift Barremian TOCA Fm. in the Lower Congo basin (West African margin). Two oriented borehole cores drilled offshore Congo were investigated using stress inversion techniques applied to calcite mechanical twins to constrain paleostress orientations and magnitudes. The inversion of calcite twins was performed on a widespread early diagenetic cement (~129 to ~113 Ma) and revealed that the TOCA Fm. has undergone a complex polyphase stress history, including (1) extensional stress regimes with vertical σ 1 and horizontal σ 3 trending NE-SW and WNW-ESE (N100) associated with the rifting episode preceding the opening of the South Atlantic (130 to 112 Ma), and with mean differential stresses of ~47 MPa for (σ 1 -σ 3) and ~ 20 MPa for (σ 2 -σ 3). The early N100 extension is associated with the development of normal faults striking N-S that likely reactivated inherited basement structures. The direction of extension evolved during the Barremian into the main NE-SW extension marked by the dominant normal faults striking NW-SE. (2) Compressional and strike-slip stress regimes with horizontal σ 1 oriented ~N-S possibly related to the far-field intraplate transmission of orogenic stresses generated at the distant Africa-Eurasia plate boundary at ~67–60 Ma, and with mean differential stresses of 40 MPa for (σ 1 -σ 3) and 28 MPa for (σ 2 -σ 3). (3) Compressional and strike-slip stress regimes with horizontal σ 1 oriented ENE-WSW to ~E-W that we tentatively relate to the mid-Atlantic ridge push and prevailing since ~15 Ma onwards, associated with mean differential stresses of ~45 MPa for (σ 1 -σ 3) and ~ 18 MPa for (σ 2 -σ 3). Our results reveal that the TOCA Fm. recorded mainly far-field stress effects that could be related to interactions between the African plate and surrounding plates, and that divergent passive margins may experience a complex tectonic history including both extensional and compressional events. • Calcite twin inversion is used to reconstruct paleostress history on the West Africa passive margin. • The orientations and magnitudes of paleostresses affecting the syn -rift TOCA Fm. are characterized from two offshore cores in the Lower Congo basin. • The timing of the successive stress regimes in the TOCA Fm. is constrained. • The influence of far-field tectonic and gravitational lithospheric stresses transferred from distant plate boundaries on the post-rift history on the West Africa passive margin is demonstrated. [ABSTRACT FROM AUTHOR]