Excel CSV. file with more than 1,048,576 rows of data

You should try delimit it can open up to 2 billion rows and 2 million columns very quickly has a free 15 day trial too. Does the job for me!

I would suggest to load the .CSV file in MS-Access.

With MS-Excel you can then create a data connection to this source (without actual loading the records in a worksheet) and create a connected pivot table. You then can have virtually unlimited number of lines in your table (depending on processor and memory: I have now 15 mln lines with 3 Gb Memory).

Additional advantage is that you can now create an aggregate view in MS-Access. In this way you can create overviews from hundreds of millions of lines and then view them in MS-Excel (beware of the 2Gb limitation of NTFS files in 32 bits OS).

Excel 2007+ is limited to somewhat over 1 million rows ( 2^20 to be precise), so it will never load your 2M line file. I think that the technique you refer to as splitting is the built-in thing Excel has, but afaik that only works for width problems, not for length problems.

The really easiest way I see right away is to use some file splitting tool - there's tons of 'em and use that to load the resulting partial csv files into multiple worksheets.

ps: "excel csv files" don't exist, there are only files produced by Excel that use one of the formats commonly referred to as csv files...