We explore the kinematics of the stars, ionized gas, and warm molecular gas in the Seyfert 2 galaxy Mrk~3 (UGC~3426) on nuclear and galactic scales with {it Gemini} Near-Infrared Field Spectrograph (NIFS) observations, previous {it Hubble Space Telescope} data, and new long-slit spectra from the {it Apache Point Observatory} ({it APO}) 3.5 m telescope. The {it APO} spectra are consistent with our previous suggestion that a galactic-scale gas/dust disk at PA $=$ 129arcdeg, offset from the major axis of the host S0 galaxy at PA $=$ 28arcdeg, is responsible for the orientation of the extended narrow-line region (ENLR). The disk is fed by an H~I tidal stream from a gas-rich spiral galaxy (UGC~3422) $sim$100 kpc to the NW of Mrk 3, and is ionized by the AGN to a distance of at least $sim$20arcsec ($sim$5.4 kpc) from the central supermassive black hole (SMBH). The kinematics within at least 320 pc of the SMBH are dominated by outflows with radial (line of sight) velocities up to 1500 km s$^{-1}$ in the ionized gas and 500 km s$^{-1}$ in the warm molecular gas, consistent with in situ heating, ionization, and acceleration of ambient gas to produce the narrow-line region (NLR) outflows. There is a disk of ionized and warm molecular gas within $sim$400 pc of the SMBH that has re-oriented close to the stellar major axis but is counter-rotating, consistent with claims of external fueling of AGN in S0 galaxies.