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We present thirty VLBI images of the TeV blazar Markarian 421 (1101+384) atfifteen epochs spanning the time range from 1994 to 1997, and at six differentfrequencies from 2.3 to 43 GHz. The imaged observations include ahigh-resolution 5 GHz VLBI Space Observatory Programme (VSOP) observation withthe HALCA satellite on 1997 November 14; full-track VLBA observations from 1994April, 1996 November, and 1997 May at frequencies between 5 and 43 GHz; sixepochs of VLBA snapshot observations at frequencies between 2 and 15 GHz fromRadio Reference Frame studies; and five geodetic VLBI observations at 2 and 8GHz from the archive of the Washington VLBI Correlator Facility located at theU.S. Naval Observatory. The dense time coverage of the images allows us tounambiguously track components in the parsec-scale jet over the observed timerange. We measure the speeds of three inner jet components located between 0.5and 5 mas from the core (0.3 to 3 pc projected linear distance) to be 0.19 +/-0.27, 0.30 +/- 0.07, and -0.07 +/- 0.07 c (H_{0}=65 km s^{-1} Mpc^{-1}). If thesole 43 GHz image is excluded, all measured speeds are consistent with nomotion. These speeds differ from tentative superluminal speeds measured byZhang & B\aa\aa th from three epochs of data from the early 1980's. Possibleinterpretations of these subluminal speeds in terms of the high Doppler factordemanded by the TeV variability of this source are discussed.Comment: 18 pages, including 7 figures, emulateapj.sty, accepted by The  Astrophysical Journal; modified text describing Radio Reference Frame  observation

VSOP and Ground‐based VLBI Imaging of the TeV Blazar Markarian 421 at Multiple Epochs