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We present deep Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2)optical observations obtained as part of the ACS Nearby Galaxy Survey Treasury(ANGST) as well as early release Wide Field Camera 3 (WFC3) ultra-violet andinfrared observations of the nearby dwarf starbursting galaxy NGC 4214. Ourdata provide a detailed example of how covering such a broad range inwavelength provides a powerful tool for constraining the physical properties ofstellar populations. The deepest data reach the ancient red clump at M_F814W-0.2. All of the optical data reach the main sequence turnoff for stars youngerthan ~300 Myr, and the blue He burning sequence for stars younger than 500 Myr.The full CMD-fitting analysis shows that all three fields in our data set areconsistent with ~75% of the stellar mass being older than 8 Gyr, in spite ofshowing a wide range in star formation rates at the present day. Thus, ourresults suggest that the scale length of NGC 4214 has remained relativelyconstant for many Gyr. As previously noted by others, we also find the galaxyhas recently ramped up production, consistent with its bright UV luminosity andits population of UV-bright massive stars. In the central field we find UVpoint sources with F336W magnitudes as bright as -9.9. These are as bright asstars with masses of at least 52-56 M_sun and ages near 4 Myr in stellarevolution models. Assuming a standard IMF, our CMD is well-fitted by anincrease in star formation rate beginning 100 Myr ago. The stellar populationsof this late-type dwarf are compared with those of NGC 404, an early-type dwarfthat is also the most massive galaxy in its local environment. The late-typedwarf appears to have a similar high fraction of ancient stars, suggesting thatthese dominant galaxies may form at early epochs even if they have low totalmass and very different present-day morphologies.

The ACS Nearby Galaxy Survey Treasury VII. The NGC 4214 Starburst and the Effects of Star Formation History on Dwarf Morphology