Polycrystalline nickel has been deformed at room temperature by equal channel angular pressing (ECAP). ECAP was done by ten passes with alternately rotating the sample 90degrees and 180degrees after each pass about the channel axis. The final texture has been measured by X-ray diffraction. It is characterized by two twin-related components with a common {111} plane and <110> direction. The texture has a rotation sense coinciding with that of the ECAP process, yielding a triclinic sample symmetry. The grain and subgrain size distribution can be described by a log-normal function with a mean grain size and subgrain size of 550 and 150 nm, respectively. A detailed diffraction profile analysis yields a mean size of coherently scattering regions of about 60 nm, a root mean square (rms) internal stress of 140 MPa and rms internal strains in the order of magnitude of 10(-3) as well as a mean dislocation density of about 1x10(15) m(-2). The results are discussed with regard to the mechanical properties of such an advanced material.