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Discrepant measurements of the Universe's expansion rate ($H_0$) may signalphysics beyond the standard cosmological model. Here I describe two earlymodified gravity mechanisms that reconcile the value of $H_0$ by increasing theexpansion rate in the era of matter-radiation equality. These mechanisms, basedon viable Horndeski theories, require significantly less fine-tuned initialconditions than early dark energy with oscillating scalar fields. In ImperfectDark Energy at Equality (IDEE), the initial energy density dilutes slower thanradiation but faster than matter, naturally peaking around the era of equality.The minimal IDEE model, a cubic Galileon, is too constrained by the cosmicmicrowave background (Planck) and baryon acoustic oscillations (BAO) to relievethe $H_0$ tension. In Enhanced Early Gravity (EEG), the scalar field valuemodulates the cosmological strength of gravity. The minimal EEG model, anexponentially coupled cubic Galileon, gives a Planck+BAO value $H_0=68.7 \pm1.5$ (68\% c.l.), reducing the tension with SH0ES from $4.4\sigma$ to$2.6\sigma$. Additionally, Galileon contributions to cosmic acceleration mayreconcile $H_0$ via Late-Universe Phantom Expansion (LUPE). Combining LUPE, EEGand $\Lambda$ reduces the tension between Planck, BAO and SH0ES to $2.5\sigma$.I will also describe additional tests of coupled Galileons based on localgravity tests, primordial element abundances and gravitational waves. Whilefurther model building is required to fully resolve the $H_0$ problem andsatisfy all available observations, these examples show the wealth ofpossibilities to solve cosmological tensions beyond Einstein's GeneralRelativity.

Gravity in the Era of Equality: Towards solutions to the Hubble problem without fine-tuned initial conditions