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We explore the chemodynamical properties of a sample of barred galaxies inthe Auriga magneto-hydrodynamical cosmological zoom-in simulations, which formboxy/peanut (b/p) bulges, and compare these to the Milky Way (MW). We show thatthe Auriga galaxies which best reproduce the chemodynamical properties ofstellar populations in the MW bulge have quiescent merger histories sinceredshift $z\sim3.5$: their last major merger occurs at $t_{\rmlookback}>12\,\rm Gyrs$, while subsequent mergers have a stellar mass ratio of$\leq$1:20, suggesting an upper limit of a few percent for the mass ratio ofthe recently proposed Gaia Sausage/Enceladus merger. These Auriga MW-analogueshave a negligible fraction of ex-situ stars in the b/p region ($<1\%$), withflattened, thick disc-like metal-poor stellar populations. The average fractionof ex-situ stars in the central regions of all Auriga galaxies with b/p's is 3%-- significantly lower than in those which do not host a b/p or a bar. Whilethe central regions of these barred galaxies contain the oldest populations,they also have stars younger than 5Gyrs (>30%) and exhibit X-shaped age andabundance distributions. Examining the discs in our sample, we find that insome cases a star-forming ring forms around the bar, which alters themetallicity of the inner regions of the galaxy. Further out in the disc,bar-induced resonances lead to metal-rich ridges in the $V_{\phi}-r$ plane --the longest of which is due to the Outer Lindblad Resonance. Our resultssuggest the Milky Way has an uncommonly quiet merger history, which leads to anessentially in-situ bulge, and highlight the significant effects the bar canhave on the surrounding disc.

Chemodynamics of barred galaxies in cosmological simulations: On the Milky Way's quiescent merger history and in-situ bulge