This paper reports on a design experiment (Brown, 1992) where we explored how providing a linguistic support for understanding historical documents affected students comprehension of historical documents and their disciplinary literacy. The functional approach to disciplinary literacy parallels historians' reading practices while supporting language development. This language development is assisted through the discussion of difficult texts and complex issues using linguistic tools that support the development of metalinguistic awareness (see e.g. Schleppegrell, Achugar, & Oteiza, 2004). We collected data documenting the intervention (disciplinary literacy lessons) and students' performance (pre and post test of reading comprehension tasks) from five multilingual history classrooms taught by the same teacher. The data were analyzed using qualitative and quantitative methods to determine the characteristics of the disciplinary literacy lessons and students' learning. The analysis of the data shows students expanded their linguistic resources and had a deeper understanding of historical texts at the end of the semester. The case studies presented also show the great diversity in a population that is homogeneously labeled (i.e. being English learners), but which has different linguistic resources and experiences to work with. The detailed functional analysis of their textual production revealed how they attempt to construct a disciplinary gaze. (Contains 3 tables.)