Polycrystalline ultra-hard materials and compacts comprise an ultra-hard material body having a polycrystalline matrix of bonded together ultra-hard particles, e.g., diamond crystals, and a catalyst material disposed in interstitial regions within the polycrystalline matrix. The material microstructure is substantially free of localized concentrations, regions or volumes of the catalyst material or other substrate constituent. The body can include a region extending a depth from a body working surface and that is substantially free of the catalyst material. The compact is produced using a multi-stage HPHT process, e.g., comprising two HPHT process conditions, wherein during a first stage HPHT process the catalyst material is melted and only partially infiltrates the precursor ultra-hard material, and during a second stage further catalyst material infiltrates the precursor ultra-hard material to produce a fully sintered compact.