  Black hole X-ray binaries (BH XRBs) are ideal targets to study the connection
between accretion inflow and jet outflow. Here we present quasi-simultaneous,
multi-wavelength observations of the Galactic black hole system MAXI J1820+070,
throughout its 2018-2019 outburst. Our data set includes coverage from the
radio through X-ray bands from 17 different instruments/telescopes, and
encompasses 19 epochs over a 7 month time period, resulting in one of the most
well-sampled multi-wavelength data sets of a BH XRB outburst to date. With our
data, we compile and model the broad-band spectra of this source using a
phenomenological model that includes emission from the jet, companion star, and
accretion flow. This modeling allows us to track the evolution of the spectral
break in the jet spectrum, a key observable that samples the jet launching
region. We find that the spectral break location changes over at least
$\approx3$ orders of magnitude in electromagnetic frequency over this period.
Using these spectral break measurements, we link the full cycle of jet
behavior, including the rising, quenching, and re-ignition, to the changing
accretion flow properties as the source evolves through its different accretion
states. Our analyses show a consistent jet behavior with other sources in
similar phases of their outbursts, reinforcing that the jet quenching and
recovery may be a global feature of BH XRB systems in outburst. Our results
also provide valuable evidence supporting a close connection between the
geometry of the inner accretion flow and the base of the jet.
