We use a data-driven methodology, namely the directed acyclic graph, to uncover the contemporaneous and lagged relations between Bitcoin and other asset classes. The adopted methodology allows us to identify causal networks based on the measurements of observed correlations and partial correlations, without relying on a priori assumptions. Results from the contemporaneous analysis indicate that the Bitcoin market is quite isolated, and no specific asset plays a dominant role in influencing the Bitcoin market. However, we find evidence of lagged relationships between Bitcoin and some assets, especially during the bear market state of Bitcoin. This finding suggests that the integration between the Bitcoin and other financial assets is a continuous process that varies over time. We conduct forecast error variance decompositions and find that the influence of each of the other assets on Bitcoin over a 20-day horizon does not account for more than 11% of all innovations. JEL classifications: G11, G15 market capitalization reached more than 15.6 billion US dollars. Given evidence on the role of Bitcoin as an investment asset, the issue of its causal relationship with other financial assets such as equities, bonds, currencies, and commodities needs to be uncovered. In particular, increased or decreased interdependencies among Bitcoin and other financial assets have potential impacts on global investors' assets allocation decisions and on policymakers in countries that are likely to consider Bitcoin as official digital currencies or part of their foreign reserves. Although numerous studies have so far considered the relationship between Bitcoin and other economic and financial variables, there remains scepticism on the contemporaneous and lagged causal relationship between Bitcoin and numerous financial assets, and a lack of understanding on the integration of the Bitcoin market with the markets of other financial assets. Prior studies consider the relation between Bitcoin and a few financial assets that include: UK equities, EUR/USD, GBP/USD (Dyhrberg 2016), alternative monetary systems (Rogojanu and Badea 2014), metals and currencies (Baur et al. 2015), global macro-financial development (Ciaian et al. 2016b), energy commodities (Bouri et al. 2017c), global uncertainty (Bouri et al. 2017b), and trading volume (Balcilar et al. 2017). While Brière et al. (2015) point toward the low correlation of Bitcoin with traditional assets and commodities, they simply rely on the correlation coefficient and do not account for structural breaks. Interestingly, Bouri et al. (2017a) use a correlation approach based on the dynamic conditional correlation model of Engle (2002) and consider the relation between Bitcoin returns and the returns of several international equity market indices as well as commodities. However, the authors focus only on the hedge and safe haven property of Bitcoin by employing a pairwise dynamic correlation-based model. Similarly, Bouri et al. (2017c) consider the pairwise relation between Bitcoin returns and fl...