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We present an analysis of the ages and star-formation history of the F-typestars in the Upper Scorpius (US), Upper Centaurus-Lupus (UCL) and LowerCentaurus-Crux (LCC) subgroups of Scorpius-Centaurus. We find that 1) ourempirical isochrones are consistent with the previously published age-rank ofthe Sco-Cen subgroups, 2) LCC and UCL appear to reach the main sequence turn-onat spectral types ~F4 and ~F2, respectively. An analysis of the A-type starsshows US reaching the main sequence at about spectral type ~A3. 3) The medianages for the pre-main sequence members of UCL and LCC are 16 Myr and 17 Myr,respectively, in agreement with previous studies, however we find that 4) UpperSco is much older than previously thought. The luminosities of the F-type starsin US are typically a factor of ~2.5 less luminous than predicted for a 5 Myrold population for four sets of evolutionary tracks. We reexamine theevolutionary state and isochronal ages for the B-, A-, and G-type Upper Scomembers, and the evolved M supergiant Antares, and estimate a revised mean agefor Upper Sco of 11+/-1+/-2 Myr (statistical, systematic). Using radialvelocities and Hipparcos parallaxes we calculate a lower limit on the kinematicexpansion age for Upper Sco of >10.5 Myr (99% confidence). However, the dataare statistically consistent with no expansion. We reevaluate the inferredmasses for the known substellar companions in Upper Sco using the revised age.Specifically, we estimate the mass of 1RXS J1609-2105b to be 14^{+2}_{-3} Mjup,suggesting that it is a brown dwarf rather than a planet. Finally, we find thefraction of F-type stars exhibiting Ha emission and/or a K-band excessconsistent with accretion to be 0/17 (<19%; 95% C.L.) in US at ~11 Myr, whileUCL has 1/41 (2^{+5}_{-1}%; 68% C.L.) accretors and LCC has 1/50 (2^{+4}_{-1}%;68% C.L.) accretors at ~16 Myr and ~17 Myr, respectively. [Abridged]

A Revised Age for Upper Scorpius and The Star-Formation History Among the F-Type Members of the Scorpius-Centaurus OB Association