Fragmentation and Disruption: Ranking Cut-Points in Epistolary Networks at the Court of Henry VIII

As network analysis becomes more widely utilised amongst digital humanists to study connections between actors, so too grows the desire to quantify and measure importance and power within these interaction structures. Finding actors of structural significance holds implications not only in historical networks, uncovering people linking disparate communities or sitting at the center of information systems, but has real contemporary applications, most significantly for security and defense agencies (Ahnert et al., 2020). In his canonical paper ‘The Key Player Problem’ Stephen Borgatti suggested identifying cut-points – nodes which, when removed, separate one component of the network into two or more distinct components – as “the most obvious” means of finding those most likely to disrupt communication in the network (Borgatti, 2003).

This article develops Borgatti’s fragmentation equations into re-usable Python code, assessing the nodes selected by the NetworkX cut- point function in three measurements: the number of new components created by the removal of a cut-point; the size of the remaining Giant Component; and the average length of the shortest path in the Giant Component. In measuring the impact of a cut-points removal in several different ways, these experiments move beyond basic understandings of these cut-points as merely ‘cutting’ and demonstrates that these measures offer greater understanding not only of individual actors but the structures around them as well.