  We present results on the analysis of background field stars found in HST
WFPC2 observations of six of the old globular clusters of the Large Magellanic
Cloud. Treated as contaminants by the globular cluster analysts, we produce
V-I,V color-magnitude diagrams of the field stars and use them to explore the
LMC's star formation history. The photometry approaches V~26, well below the
turnoff of an ancient ~14 Gyr LMC population of stars. We use a
maximum-likelihood technique to fit model CMDs drawn from Bertelli et al.
(1994) isochrones to the observed CMDs. We constrain the models by the
age-metallicity relation derived from LMC clusters, test four IMF slopes, and
fit for the reddening, distance modulus, and star formation rate. We find that
we can just resolve structure in SFR(t) with time steps of ~0.15 in log age,
implying a resolution of ~4x10^8 years at an age of 1 Gyr. For a Salpeter IMF,
our derived star formation history for the NGC 1754 field is characterized by
an enhanced star formation rate over the past 4 Gyr, qualitatively resembling
that derived by others for a variety of LMC fields. The remaining four fields,
however, appear to have had high levels of star formation activity as long as
5-8 Gyr ago; these fields lie in the LMC Bar while the NGC 1754 field lies in
the disk, suggesting that the inner regions of the LMC contain significantly
more older stars than the outer regions. Examining the residuals of the models
and observations, we find that the old red giant branches of the models provide
a poor fit to the observations, which suggests an error in the model
isochrones. The effect of the disagreement appears to be to underestimate the
contribution of the old population.
