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The spectrum of neutral iron is critical to astrophysics, yet furnacelaboratory experiments cannot reach many high-lying Fe I levels. Instead,Peterson & Kurucz (2015) and Peterson, Kurucz & Ayres (2017) turned to UV andoptical spectra of warm stars to identify and assign energies for 124 Fe Ilevels with 1900 detectable Fe I lines, and to derive astrophysical gf valuesfor over a thousand of these. An energy value was assumed for each unknown Fe Ilevel, and confirmed if it shifted the predicted positions in updated Kurucz(2011) Fe I calculations to match exactly in wavelength the positions of fouror more unidentified lines in the observed spectra. Nearly all theseidentifications were for LS levels characterized by spin-orbit coupling, whoselines fall primarily at UV and optical wavelengths. This extension of thesesearches provides nearly a hundred new Fe I level identifications. Thirty-nineLS levels are identified largely by incorporating published positions ofunidentified laboratory Fe I lines with wavelengths < 2000A. Adding infraredspectra provided sixty Fe I jK levels, where a single isolated outer electronorbits a compact core. Their weak, blended lines fall mostly in the infrared,but are searchable because their mutual energies obey tight relationships. Foreach new Fe I level, this work again provides and makes publicly available itsidentification, its energy, and a list of over 16,000 of its potentiallydetectable lines with theoretical gf values. For over 2,000 of these, this workalso includes astrophysical gf values, ones adjusted semi-empirically to fitthe stellar spectra. The potential impact of this work on modeling UV and IRstellar spectra is noted.

New Fe I Level Energies and Line Identifications from Stellar Spectra. III. Initial Results from UV, Optical, and Infrared Spectra