We examine international stock return comovements using country-industry and country-style portfolios as the base portfolios. We first establish that parsimonious risk-based factor models capture the data covariance structure better than the popular Heston–Rouwenhorst (1994) model. We then establish the following stylized facts regarding stock return comovements. First, there is no evidence for an upward trend in return correlations, except for the European stock markets. Second, the increasing importance of industry factors relative to country factors was a short-lived phenomenon. Third, large growth stocks are more correlated across countries than are small value stocks, and the difference has increased over time.

We identify the relative importance of changes in the conditional variance of fundamentals (which we call “uncertainty”) and changes in risk aversion in the determination of the term structure, equity prices, and risk premiums. Theoretically, we introduce persistent time-varying uncertainty about the fundamentals in an external habit model. The model matches the dynamics of dividend and consumption growth, including their volatility dynamics and many salient asset market phenomena. While the variation in price–dividend ratios and the equity risk premium is primarily driven by risk aversion, uncertainty plays a large role in the term structure and is the driver of countercyclical volatility of asset returns.

ABSTRACT We examine international stock return comovements using country‐industry and country‐style portfolios as the base portfolios. We first establish that parsimonious risk‐based factor models capture the data covariance structure better than the popular Heston–Rouwenhorst (1994) model. We then establish the following stylized facts regarding stock return comovements. First, there is no evidence for an upward trend in return correlations, except for the European stock markets. Second, the increasing importance of industry factors relative to country factors was a short‐lived phenomenon. Third, large growth stocks are more correlated across countries than are small value stocks, and the difference has increased over time.