  We establish the three-dimensional architecture of the Kepler-419 (previously
KOI-1474) system to be eccentric yet with a low mutual inclination. Kepler-419b
is a warm Jupiter at semi-major axis a = 0.370 +0.007/-0.006 AU with a large
eccentricity e=0.85 +0.08/-0.07 measured via the "photoeccentric effect." It
exhibits transit timing variations induced by the non-transiting Kepler-419c,
which we uniquely constrain to be a moderately eccentric (e=0.184 +/- 0.002),
hierarchically-separated (a=1.68 +/- 0.03 AU) giant planet (7.3 +/- 0.4 MJup).
We combine sixteen quarters of Kepler photometry, radial-velocity (RV)
measurements from the HIgh Resolution Echelle Spectrometer (HIRES) on Keck, and
improved stellar parameters that we derive from spectroscopy and
asteroseismology. From the RVs, we measure the mass of inner planet to be
2.5+/-0.3MJup and confirm its photometrically-measured eccentricity, refining
the value to e=0.83+/-0.01. The RV acceleration is consistent with the
properties of the outer planet derived from TTVs. We find that, despite their
sizable eccentricities, the planets are coplanar to within 9 +8/-6 degrees, and
therefore the inner planet's large eccentricity and close-in orbit are unlikely
to be the result of Kozai migration. Moreover, even over many secular cycles,
the inner planet's periapse is most likely never small enough for tidal
circularization. Finally, we present and measure a transit time and impact
parameter from four simultaneous ground-based light curves from 1m-class
telescopes, demonstrating the feasibility of ground-based follow-up of Kepler
giant planets exhibiting large TTVs.
