  The prompt emission of the long, smooth, and single-pulsed gamma-ray burst,
GRB $\textit{141028A}$, is analyzed under the guise of an external shock model.
First, we fit the $\gamma$-ray spectrum with a two-component photon model,
namely synchrotron+blackbody, and then fit the recovered evolution of the
synchrotron $\nu F_{\nu}$ peak to an analytic model derived considering the
emission of a relativistic blast-wave expanding into an external medium. The
prediction of the model for the $\nu F_{\nu}$ peak evolution matches well with
the observations. We observe the blast-wave transitioning into the deceleration
phase. Further we assume the expansion of the blast-wave to be nearly
adiabatic, motivated by the low magnetic field deduced from the observations.
This allows us to recover within an order of magnitude the flux density at the
$\nu F_{\nu}$ peak, which is remarkable considering the simplicity of the
analytic model. Across all wavelengths, synchrotron emission from a single
forward shock provides a sufficient solution for the observations. Under this
scenario we argue that the distinction between $\textit{prompt}$ and $\textit{
afterglow}$ emission is superfluous as both early and late time emission
emanate from the same source. While the external shock model is clearly not a
universal solution, this analysis opens the possibility that at least some
fraction of GRBs can be explained with an external shock origin of their prompt
phase.
