This question is an interesting one and brings up several questions itself. Firstly, what actually is history ? Secondly, what is official history ? Does it differ from unofficial history ?
Obviously what is deemed history depends on the values and mores of those writing or recording history. To indigenous Australians, for example, the notion of evolving from a hunting and gathering lifestyle to a more sedentary one was never regarded as a "measurable" step in history. To white European settlers, the lack of a settled population was very important because it meant that they were dealing with a seemingly "less evolved" race of people and so were almost justified in decimating it.
The writing of history has reflected society in the past. The roles of women and minorities has been ignored or simply devalued because their deeds have not been valued.
If we look at the study of the history of World War 2, the traditional historian has focused on the heroic deeds of the soldiers or indeed the horrific actions of our foes. The result is a text (written, spoken or viewed) that tells of the battles and sacrifices made. The contributions of minority groups is largely left ignored. Until recently, the role of women on the home front, the role of the American Indian and the part played by African Americans was only cited or studied in a minority of studies. The World War 2 museum in New Orleans has made the deliberate decision to focus on the part played by all these groups.
Another question to consider,of course, is what is reported. "Official" history is designed to tell the story of a country in an easy to read/understandable manner. It is important for a country to show itself in a good light. Sometimes, it is a case of what is left out of the history that is a concern. A particular examples we can use is the history of the settlement of the USA and the brave settlers who fought all obstacles to succeed. The reported mistreatment of indigenous Americans and their culture has received scant notice.